Cosmic-ray physics in the GeV-to-TeV energy range has entered a precision era thanks to recent data from space-based experiments. However, the poor knowledge of nuclear reactions, in particular for the production of antimatter and secondary nuclei, limits the information that can be extracted from these data, such as source properties, transport in the Galaxy and indirect searches for particle dark matter. The Cross-Section for Cosmic Rays at CERN workshop series has addressed the challenges encountered in the interpretation of high-precision cosmic-ray data, with the goal of strengthening emergent synergies and taking advantage of the complementarity and know-how in different communities, from theoretical and experimental astroparticle physics to high-energy and nuclear physics. In this paper, we present the outcomes of the third edition of the workshop that took place in 2024. We present the current state of cosmic-ray experiments and their perspectives, and provide a detailed road map to close the most urgent gaps in cross-section data, in order to efficiently progress on many open physics cases, which are motivated in the paper. Finally, with the aim of being as exhaustive as possible, this report touches several other fields ─ such as cosmogenic studies, space radiation protection and hadrontherapy ─ where overlapping and specific new cross-section measurements, as well as nuclear code improvement and benchmarking efforts, are also needed. We also briefly highlight further synergies between astroparticle and high-energy physics on the question of cross-sections.

At any given scale, 3 <inline-formula><tex-math>$\times$</tex-math></inline-formula> 2-point statistics extract only three numbers from the joint distribution of the cosmic matter density and galaxy density fluctuations: their variances and their covariance. It is well known that the full shape of the probability distribution function (PDF) of those fluctuations contains significantly more information than can be accessed through these three numbers. But the study of the PDF of cosmic density fluctuations in real observational data is still in its infancy. Here we present COSMOMENTUM, a public software toolkit for calculating theoretical predictions for the full shape of the joint distribution of a line-of-sight-projected tracer density and the gravitational lensing convergence. We demonstrate that an analysis of this full shape of the PDF can indeed disentangle complicated tracer bias and stochasticity relations from signatures of cosmic structure growth. Our paper also provides back-drop for an upcoming follow-up study, which prepares PDF analyses for application to observational data by incorporating the impact of realistic weak lensing systematics.

The R3B experiment at FAIR studies nuclear reactions using high-energy radioactive beams. One key detector in R3B is the CALIFA calorimeter consisting of 2544 CsI(Tl) scintillator crystals designed to detect light charged particles and gamma rays with an energy resolution in the per cent range after Doppler correction. Precise cluster reconstruction from sparse hit patterns is a crucial requirement. Standard algorithms typically use fixed cluster sizes or geometric thresholds. To enhance performance, advanced machine learning techniques such as agglomerative clustering were implemented to use the full multi-dimensional parameter space including geometry, energy and time of individual interactions. An Edge Detection Neural Network exhibited significant differences. This study, based on Geant4 simulations, demonstrates improvements in cluster reconstruction efficiency of more than 30%, showcasing the potential of machine learning in nuclear physics experiments.

Low-energy cosmic and solar radiation serves as a probe for investigations in astrophysics and heliophysics, and at the same time constitutes a risk to the spacecraft and crew of deep-space exploration missions. We present compact tracking calorimeters made from scintillating-plastic fibers and silicon photomultipliers that can determine the charge and energy of individual cosmic-ray nuclei with energies in the MeV-to-GeV range. Their comprehensive particle-identification capabilities allow to accurately determine the radiation exposure of astronauts and have potential applications in the indirect detection of dark matter.

In this study, we perform a comparative analysis of the properties of the H II regions located in different areas of barred galaxies, with the aim of investigating the impact of bars on the physical properties of the ionized gas. Based on integral field spectroscopy data for 17 barred galaxies covering approximately the central <inline-formula><tex-math>$6\times 6$</tex-math></inline-formula> kpc, we detect a total of 2200 <inline-formula><tex-math>${\mathrm H\, {\small II}}$</tex-math></inline-formula> regions, of which 331 are located within the nuclear disc (also known as circumnuclear regions), 661 in the bar region, and 1208 in the disc. Among the physical properties of the <inline-formula><tex-math>${\mathrm H\, {\small II}}$</tex-math></inline-formula> regions, we explore the O/H and N/O abundances, H<inline-formula><tex-math>$\alpha$</tex-math></inline-formula> luminosity, dust extinction, electron density, and H<inline-formula><tex-math>$\alpha$</tex-math></inline-formula> equivalent width. We find clear differences in the properties of the <inline-formula><tex-math>${\rm H\, {\small II}}$</tex-math></inline-formula> regions between the nuclear disc, the bar, and the disc, that could be explained by an enhancement in the molecular gas concentration in the central parts driven by bar-induced gas flows. As this gas is channelled towards the galaxy centre, the most extreme values in the analysed properties are found for the circumnuclear <inline-formula><tex-math>${\rm H\, {\small II}}$</tex-math></inline-formula> regions. Unlike the bar strength, galaxy mass does seem to affect the properties of the <inline-formula><tex-math>${\rm H\, {\small II}}$</tex-math></inline-formula> regions, with massive galaxies presenting higher values in most of the properties, possibly due to the increased amount of gas in these systems. This study provides evidence that the bar-driven redistribution of material within the galaxy inner parts causes significant differences in the <inline-formula><tex-math>${\rm H\, {\small II}}$</tex-math></inline-formula> region properties depending on their location within the galaxies.

An asteroseismic analysis has revealed a magnetic field in the deep interior of a slowly rotating main-sequence F star KIC 9244992, which was observed by the Kepler spacecraft for 4 yr. The star shows clear asymmetry of frequency splittings of high-order dipolar gravity modes, which cannot be explained by rotation alone, but are fully consistent with a model with rotation, a magnetic field, and a discontinuous structure (glitch). Careful examination of the frequency dependence of the asymmetry allows us to put constraints on not only the radial component of the magnetic field but also its azimuthal (toroidal) component. The lower bounds of the root mean squares of the radial and azimuthal components in the radiative region within 50 per cent in radius, which have the highest sensitivity in the layers just outside the convective core with a steep gradient of chemical compositions, are estimated to be <inline-formula><tex-math>${\mathsf {B}_{\text{r}}^{\text{min}}}=3.5\pm 0.1\, \text{kG}$</tex-math></inline-formula> and <inline-formula><tex-math>${\mathsf {B}_{\phi }^{\text{min}}}= 92 \pm 7\, \text{kG}$</tex-math></inline-formula>, respectively. The much stronger azimuthal component than the radial one is consistent with the significant contribution of the differential rotation, although the star has almost uniform rotation at present. The estimated field strengths are too strong to be explained by dynamo mechanisms in the radiative zone associated with the magnetic Tayler instability. The aspherical glitch is found to be located in the innermost radiative layers where there is a steep gradient of chemical composition. The first detection of magnetic fields in the deep interior of a main-sequence star sheds new light on the problem of stellar magnetism, for which there remain many uncertainties.

The first four all-sky surveys with eROSITA the soft X-ray instrument on board the Spektrum-Roentgen-Gamma (SRG) satellite revealed a new X-ray source, eRASSU J012422.9-724248, in the Magellanic Bridge, near the Eastern Wing of the Small Magellanic Cloud (SMC). We performed a broadband timing and spectral analysis using the optical and X-ray data of eRASSU J012422.9-724248. Using the X-ray observations with eROSITA, Swift, NuSTAR and optical data from the optical Gravitational Lensing Experiment (OGLE) and the Las Cumbres Observatory (LCO), we confirm the nature of eRASSU J012422.9-724248 as a Be/X-ray binary (BeXRB) pulsar in the Magellanic bridge. The position is coincident with that of an early-type star (OGLE ID SMC732.10.7). We detect the spin period at 341.71 s in NuSTAR data and infer a period of 63.65 days from the 15 year monitoring with OGLE, that we interpret as the orbital period of the system. A tentative CRSF at ~12.3 keV is identified in NuSTAR spectra with ~1.8-sigma. The source appears to show a persistent X-ray luminosity and an optical magnitude transition on the long timescale. We propose eRASSU J012422.9-724248 is a new member of the class of persistent BeXRBs.

We derive a general expression for the resummation of rapidity distributions for processes with a colorless final state, such as Drell-Yan or Higgs production, in the limit in which the center-of-mass energy goes on threshold, but with fixed rapidity of the Higgs or gauge boson in the partonic center-of-mass frame. The result is obtained by suitably generalizing the renormalization-group based approach to threshold resummation previously pursued by us. The ensuing expression is valid to all logarithmic orders but the resummation coefficients must be determined by comparing to fixed order results. We perform this comparison for the Drell-Yan process using the fixed-order next-to-next-to-leading (NNLO) result, thereby determining resummation coefficients up to next-to-next-to-leading logarithmic (NNLL) accuracy, for the quark-antiquark coefficient function in the quark nonsinglet channel. We provide a translation to direct QCD of a result for this resummation previously obtained using SCET methods, and we show that it agrees with our own.

Chemical reaction networks are central to all chemical models. Each rate coefficient has an associated uncertainty, which is generally not taken into account when calculating the chemistry. We performed the first uncertainty analysis of a chemical model of C- and O-rich asymptotic giant branch (AGB) outflows using the RATE22 reaction network. Quantifying the error on the model predictions enables us to determine the need for adding complexity to the model. Using a Monte Carlo sampling method, we quantified the impact of the uncertainties on the chemical kinetic data on the predicted fractional abundances and column densities. The errors are caused by a complex interplay of reactions forming and destroying each species. Parent species show an error on their envelope sizes, which is not caused by the uncertainty on their photodissociation rate, but rather the chemistry reforming the parent after its photodissociation. Using photodissociation models to estimate the envelope size might be an oversimplification. The error on the CO envelope impacts retrieved mass-loss rates by up to a factor of two. For daughter species, the error on the peak fractional abundance ranges from a factor of a few to three orders of magnitude, and is on average about 10 per cent of its value. This error is positively correlated with the error on the column density. The standard model suffices for many species, e.g. the radial distribution of cyanopolyynes and hydrocarbon radicals around IRC +10216. However, including spherical asymmetries, dust-gas chemistry, and photochemistry induced by a close-by stellar companion are still necessary to explain certain observations.

We aim to evaluate how well the variation of small-scale magnetic fields on the stellar surface can be monitored with time-series observations. Further, we aim to establish to what extent the measured total unsigned magnetic field traces other activity indicators. We measured the total unsigned magnetic field on four young, stars using Zeeman splitting of magnetically sensitive spectral lines from high-resolution spectra obtained with the spectropolarimeters ESPaDOnS at CFHT and NARVAL at TBL. We then characterised the magnetic field variations using both sinusoidal variation and Lomb-Scargle periodograms. We evaluated how the rotational variation of the total unsigned magnetic field strength correlates with the activity indicators S-index, H$α$-index, Ca IRT-index, and the large-scale magnetic field obtained from ZDI maps obtained in earlier studies. We find clear signals of rotational modulation of the total magnetic field on HIP 76768 and tentative detection on Mel 25-5. This is supported both by the sinusoidal fitting and the periodogram. For the other stars, we find no modulation signals of the total magnetic field. We find positive correlations between the total magnetic field and activity indices on all four stars, indicating that indirect magnetic activity indicators trace the underlying magnetic field variability. However, comparing the activity-magnetic field relationship between the stars in our sample shows a significant deviation between activity level and measured magnetic field strength. Small-scale magnetic field variability can be traced using the Zeeman effect on magnetically sensitive lines, provided that the star is sufficiently active. It is also possible to self-consistently recover rotational periods from such measurements. The primary limit for the detection of magnetic field variations is the precision of Zeeman broadening and intensification measurements.

This proceedings paper briefly reviews the status of direct experimental probes into the neutrino-mass scale, with an emphasis on recent results from the KATRIN experiment.

We provide an explicit construction of a manifestly duality invariant, interacting deformation of Maxwell theory in four dimensions in terms of mutually local, but interacting 1- and 3-forms. Interestingly, our theory is formulated directly as a BRST quantized gauge theory, while the underlying gauge invariant Lagrangian before gauge fixing is obscured. Furthermore, the underlying gauge invariance is based on an associative, rather than a Lie symmetry.

Active galactic nuclei (AGNs) drive powerful, multiphase outflows that are thought to play a key role in galaxy evolution. The hot, shocked phase of these outflows (<inline-formula><tex-math>$T{\gtrsim }10^{6}{\rm {\ K}}$</tex-math></inline-formula>) is expected to dominate the energy content, but is challenging to observe due to its long cooling time and low emissivity. The cool phase (<inline-formula><tex-math>$T{\lesssim }10^{4}{\rm {\ K}}$</tex-math></inline-formula>) is easier to detect observationally, but it traces a less energetic outflow component. In prior simulations of the interaction between an energy-driven AGN outflow and a clumpy ISM, we found that mixing between hot wind and cool ISM clouds produces a new, highly radiative, phase at <inline-formula><tex-math>$T{\approx }10^{6-7}{\rm {\ K}}$</tex-math></inline-formula> which fuels the formation of a long-lived (<inline-formula><tex-math>$\ge 5\ \rm {Myr}$</tex-math></inline-formula>) cool outflow. We investigate the X-ray emission generated by thermal Bremsstrahlung and high-ionization metal line emission in this mixing phase, finding that it could contribute significantly to the X-ray output of the outflow. This mixing-induced X-ray emission is strongest in the part of the outflow propagating equatorially through the disc, and is extended on scales of <inline-formula><tex-math>$D\simeq 3\!-\!4\ \rm {kpc}$</tex-math></inline-formula>. For quasar luminosities of <inline-formula><tex-math>$L_{\rm {AGN}}{\simeq } 10^{45-46}\rm {\ erg\ s^{-1}}$</tex-math></inline-formula>, the resulting X-ray luminosity is equivalent to that expected from star formation rates <inline-formula><tex-math>$\rm {SFR}\simeq 10\!-\!200\ \rm {M_\odot \ yr^{-1}}$</tex-math></inline-formula>, showing that it could be an important source of soft X-rays in AGN host galaxies. Our results suggest that this extended emission could be resolvable in local quasars (<inline-formula><tex-math>$z\lesssim 0.11$</tex-math></inline-formula>) using high spatial-resolution X-ray observatories such as Chandra, or proposed missions such as AXIS and Lynx.

We present an implementation of radiative transfer with flux-limited diffusion (FLD) for the moving-mesh code AREPO and use the method in a physical model for the formation of protostars with non-ideal radiation-magnetohydrodynamics (RMHD). We follow previous work in splitting the additional terms to the hydrodynamical equations arising from the inclusion of radiation into terms to be integrated explicitly and implicitly, as the diffusion and coupling terms would impose very restrictive time-step criteria. We validate the scheme with standard test problems for radiation diffusion, matter─gas coupling, and radiative shocks from the literature. Our implementation is compatible with local time-stepping, which often presents problems for implicit schemes, and we found very good agreement with results obtained with global time-steps. We present an example application of the new implementation to the collapse of a <inline-formula><tex-math>$1\, {\rm M}_\odot$</tex-math></inline-formula> molecular cloud core to a second Larson core modelled with radiation non-ideal magnetohydrodynamics. A high-velocity jet with v<inline-formula><tex-math>$_{\rm rad}> 10\, {\rm km\, s^{-1}}$</tex-math></inline-formula> is self-consistently launched from the second core, nested within the first core, which produces a lower-velocity magnetorotational outflow. We observe magnetic field amplification up to more than <inline-formula><tex-math>$\vert \mathbf {B}\vert _{\rm max}>10^5$</tex-math></inline-formula> G in the second core, which is surrounded by a small (<inline-formula><tex-math>$< 0.5$</tex-math></inline-formula> au) disc. This application demonstrates the robustness of our scheme in multiscale and high-resolution simulations on arbitrary meshes and, as such, the model can be readily used for further simulations of protostar formation at high resolution.

We present the equation of state for two classes of new ultralight particles, a scalar field coupling to electrons and a light <inline-formula><tex-math>$\mathbb {Z}_\mathcal {N}$</tex-math></inline-formula> QCD axion field coupling to nucleons. Both are potential candidates for dark matter. Using the scalar modified equations of state, we calculate models for white dwarf stars and compare their radii and masses with observed mass─radius data. The comparison results in stringent constraints on the masses of the particles and the coupling parameters. For a wide range of particle masses and coupling parameters, constraints from the white dwarf equation of state surpass existing limits, outperforming also dedicated laboratory searches. The remarkable accuracy of modern white-dwarf mass─radius relation data, exemplified by Sirius B, now allows stringent tests of dense-matter physics and constraints on new particle scenarios.

We explore the formation of intermediate mass black holes (IMBHs), potential seeds for supermassive black holes (SMBHs), via runaway stellar collisions for a wide range of star cluster (surface) densities ($4\times10^3 M_\odot$ pc$^{-2} \lesssim Σ_\mathrm{h}$ $\lesssim 4\times10^6 M_\odot$ pc$^{-2}$) and metallicities ($0.01 Z_\odot \lesssim Z \lesssim 1.0 Z_\odot)$. Our sample of isolated $(>1400)$ and hierarchical ($30$) simulations of young, massive star clusters with up to $N=1.8\times10^6$ stars includes collisional stellar dynamics, stellar evolution, and post-Newtonian equations of motion for black holes using the BIFROST code. High stellar wind rates suppress IMBH formation at high metallicities $(Z \gtrsim 0.2 Z_\odot)$ and low collision rates prevent their formation at low densities ($Σ_\mathrm{h} \lesssim 3\times10^4 M_\odot$ pc$^{-2}$). The assumptions about stellar wind loss rates strongly affect the maximum final IMBH masses $(M_\bullet \sim 6000 M_\odot$ vs. $25000 M_\odot$). The total stellar mass loss from collisions and collisionally boosted winds before $t=3$ Myr can together reach up to 5-10% of the final cluster mass. We present fitting formulae for IMBH masses as a function of host star cluster $Σ_\mathrm{h}$ and Z, and formulate a model for the cosmic IMBH formation rate density. Depending on the cluster birth densities, the IMBH formation rates peak at $z\sim2$-$4$ at up to $\sim10^{-7}$ yr$^{-1}$cMpc$^{-3}$. As more than 50% form below $z\lesssim1.5$-$3$, the model challenges a view in which all local IMBHs are failed early Universe SMBH seeds.

We investigate whether photoevaporation alone can open and sustain gaps in protoplanetary discs by coupling the evolving disc structure with the photoevaporative flow in two dimensional radiation hydrodynamical simulations. Our results show that once a density depression forms, the local mass-loss rate decreases sharply, suppressing further gap deepening. Viscous inflow and radial mass transport along the disc surface act to partially refill the depleted region, preventing complete clearing. The resulting configuration is a persistent, partially depleted zone whose evolution is largely insensitive to the initial disc morphology. This behaviour challenges the standard paradigm that photoevaporation efficiently carves clean inner cavities and directly produces transition discs. However, the pressure maximum at the outer edge of the depression may still trap dust grains, giving rise to transition disc like observational signatures. We also present a first-order prescription to approximate this behaviour in one dimensional disc evolution models, suitable for use in planet formation and population synthesis studies. Although the prescription improves upon static mass-loss treatments, it remains approximate, underscoring the need for further multidimensional simulations and parameter-space exploration to derive robust recipes for global disc and planet population models.

Changing-state active galactic nuclei (CSAGNs) exhibit rapid variability, with mass accretion rates that can change by several orders of magnitude in a few years. This provides us with a unique opportunity to study the evolution of the inner accretion flow almost in real time. Here, we used over 1000 observations to study the broadband X-ray spectra of a sample of five CSAGNs, spanning three orders of magnitude in Eddington ratio ($λ_{\rm Edd}$), using phenomenological models to trace the evolution of key spectral components. We derive several fundamental parameters, such as the photon index, soft excess strength, reflection strength, and luminosities of the soft excess and primary continuum. We find that the soft excess and primary continuum emissions show a very strong positive correlation ($p \ll 10^{-10}$), suggesting a common physical origin. The soft excess strength does not show any dependency on the reflection parameter, suggesting that in these objects the soft excess is not dominated by a blurred ionized reflection process. On the other hand, the strength of the soft excess is found to be strongly positively correlated with the Eddington ratio ($p \ll 10^{-10}$), and we find that the soft excess vanishes below $\log λ_{\rm Edd} \sim -2.5$. Moreover, we find a clear `V'-shaped relation for $Γ-λ_{\rm Edd}$, with a break at $\log λ_{\rm Edd} = -2.47 \pm 0.09$. Our findings indicate a change in the geometry of the inner accretion flow at low Eddington ratios, and that the soft excess is primarily produced via warm Comptonization.

Context. Cosmic voids are a promising probe of cosmology for spectroscopic galaxy surveys due to their unique response to cosmological parameters. Their combination with other probes promises to break parameter degeneracies. Aims. Due to simplifying assumptions, analytical models for void statistics represent only a subset of the full void population. We present a set of neural-based emulators for void summary statistics of watershed voids, which retain more information about the full void population than simplified analytical models. Methods. We built emulators for the void size function and void density profiles traced by the halo number density using the QUIJOTE suite of simulations that spans a wide range of the Λ cold dark matter (ΛCDM) parameter space. The emulators replace the computation of these statistics from computationally expensive cosmological simulations. We demonstrate the cosmological constraining power of voids using our emulators, which offer orders-of-magnitude acceleration in parameter estimation, capture more cosmological information compared to analytical models, and produce more realistic posteriors compared to Fisher forecasts. Results. In this QUIJOTE setup, we recover the parameters Ω_m and σ₈ to within 14.4% and 8.4% accuracy, respectively, using void density profiles. Incorporating additional information from the void size function improves the accuracy for σ₈ to 6.8%. We demonstrate the robustness of our approach with respect to two important variables in the underlying simulations: the resolution and the inclusion of baryons. We find that our pipeline is robust to variations in resolution, and we show that the posteriors derived from the emulated void statistics are unaffected by the inclusion of baryons in the Magneticum hydrodynamic simulations. This opens up the possibility of a baryon-independent probe of the large-scale structure.

The initial mass function (IMF) is a cornerstone of star formation studies, yet its universality remains debated. We investigate the IMF in the young massive cluster RCW 36, located in the Vela Molecular Ridge and comparable to the Orion Nebula Cluster in stellar density. Our goal is to build the most complete census of RCW 36 and derive its first IMF and star-to-brown-dwarf (BD) ratio. We combine new GLAO observations from HAWK-I/VLT with archival data (2MASS, SOFI/NTT) and Gaia DR3 kinematics. Photometric accuracy and source extraction were improved using \textsc{DeNeb}, a deep-learning algorithm that removes complex nebular emission. Membership probabilities were assigned via color-magnitude diagram comparisons with a control field, and stellar masses were estimated using model isochrones. We find a revised distance of $954\pm40\,$pc and determine the IMF down to $\sim0.03\,M_{\odot}$, described by a broken power law ($dN/dM\propto M^{-α}$) with $α=1.62\pm0.03$ for $0.20$-$20\,M_{\odot}$ and $α=0.46\pm0.14$ for $0.03$-$0.20\,M_{\odot}$. The star-BD ratio is $2$-$5$, consistent with other Galactic clusters. Lastly, through a study of the differences in the IMF within and outside $0.2\,$pc and the cumulative mass distributions for low-mass and intermediate to high-mass sources, we also detected signs of possible mass segregation within RCW 36, which should be primordial. RCW 36 shares many characteristics with other young massive clusters, such as a shallower than Salpeter high-mass slope and the possibility of mass segregation. The flatter lower-mass regime of the IMF is similar to most Galactic clusters. The star-BD ratio is also in line with the observed values in other clusters, independent of their inherent properties.

The tidal disruption of planets by their host stars represents a growing area of interest in transient astronomy, offering insights into the final stages of planetary system evolution. We model the hydrodynamic evolution and predict the multi-wavelength observational signatures of planetary TDEs around a solar-mass host, focusing on Jupiter-like and Neptune-like progenitors and examining how different eccentricities of the planet's pre-disruption orbit shape the morphology and emission of the tidal debris.We perform 2D hydrodynamic simulations using the FARGO3D code to model the formation and viscous evolution of the resulting debris disk. We employ a viscous alpha-disk prescription and include a time-dependent energy equation to compute the disk's effective temperature and subsequently derive the bolometric and multi-band photometric light curves.Our simulations show that planetary TDEs produce a diverse range of luminous transients. A Jupiter-like planet disrupted from a circular orbit at the Roche limit generates a transient peaking at $L_{bol} \approx 10^{38}$ erg s$^{-1}$ after a 12-day rise. In contrast, the same planet on an eccentric orbit (e=0.5) produces a transient of comparable peak luminosity but on a much shorter timescale, peaking in only 1 day and followed by a highly volatile light curve. We find that the effect of eccentricity is not universal, as it accelerates the event for Jupiter but delays it for Neptune. A robust "bluer-when-brighter" colour evolution is a common feature as the disk cools over its multi-year lifetime. The strong dependence of light curve morphology on the initial orbit and progenitor mass makes these events powerful diagnostics. This framework is crucial for identifying planetary TDEs in time-domain surveys.

Tidal features provide signatures of recent galaxy mergers, offering insights into the role of mergers in galaxy evolution. The Vera C. Rubin Observatory's upcoming Legacy Survey of Space and Time (LSST) will allow for an unprecedented study of tidal features around millions of galaxies. We use mock images of galaxies at <inline-formula><tex-math>$z\sim 0$</tex-math></inline-formula> (<inline-formula><tex-math>$z\sim 0.2$</tex-math></inline-formula> for NEWHORIZON) from NEWHORIZON, EAGLE, ILLUSTRISTNG, and MAGNETICUM PATHFINDER simulations to predict the properties of tidal features in LSST-like images. We find that tidal features are more prevalent around blue galaxies with intrinsic colours <inline-formula><tex-math>$(g-i)\le 0.5$</tex-math></inline-formula>, compared to redder ones, at fixed stellar mass. This trend correlates with elevated specific star formation rates (<inline-formula><tex-math>$\mathrm{sSFR}>10^{-10}\mathrm{\:yr}^{-1}$</tex-math></inline-formula>), suggesting that merger-induced star formation contributes to the bluer colours. Tidal feature hosts in the red sequence appear to exhibit colour profiles offset to bluer colours for galaxies with stellar masses <inline-formula><tex-math>$10^{10}< M_{\star \mathrm{,\:30\:pkpc}}/\mathrm{M}_\odot < 10^{11}$</tex-math></inline-formula>, similarly blue cloud tidal feature host galaxies appear to have their colour profiles offset to bluer colours for <inline-formula><tex-math>$10^{9.5}< M_{\star \mathrm{,\:30\:pkpc}}/\mathrm{M}_\odot < 10^{10.5}$</tex-math></inline-formula>. However, the differences in colour profiles in either the red sequence or the blue cloud are not statistically robust and larger samples are needed to test if these differences are real. The predictions across the simulations are quantitatively distinct; therefore, LSST observations will allow us to further constrain the differences between different subgrid physics models.

The calculation of precise predictions for Higgs decays is a necessary ingredient for determining Higgs properties at the LHC and future colliders. We compute all two- and three-body Higgs decays at next-to-leading order (NLO) in both QCD and electroweak interactions using the dimension-6 Standard Model Effective Field Theory (SMEFT). Results for four-body Higgs decays that are accurate to NLO QCD/electroweak order in the SMEFT are obtained using the narrow width approximation. Our results are contained in a flexible Monte Carlo program, NEWiSH, that is publicly available and we illustrate the impact of the NLO electroweak corrections for HL-LHC, Tera-Z, and Higgstrahlung projections.

The AMBER experiment at CERN will measure the proton’s charge radius via muon-proton elastic scattering at high projectile energies and small momentum transfers to help to resolve the so-called proton radius puzzle, i.e., the discrepancy between charge radii measured with different experimental techniques. The core setup at AMBER consists of a hydrogen-filled time projection chamber (TPC). Tracking detectors upstream and downstream of the TPC measure the trajectories of the incoming and outgoing muons to determine their scattering angles. To resolve pile-up hits in the tracking detectors, we are constructing four high-granularity hodoscopes from 500-<math altimg="si1.svg" display="inline" id="d1e204"><mrow><mi mathvariant="normal">μ</mi><mi mathvariant="normal">m</mi></mrow></math> scintillating-plastic fibers and arrays of silicon photomultipliers. In this contribution, we present the design of the scintillating-fiber hodoscopes and first results of test-beam measurements with scaled-down prototypes. We will particularly emphasize how we managed to design detectors with a low material budget.

The measurement of dust size from millimeter-wavelength spectra provides direct constraints on grain growth in protoplanetary disks. Spectral indices between 0.88 and 2.9 mm have been measured in multiple young star-forming regions, such as Taurus, Ophiuchus, and Lupus, which have ages of 1-3 Myr. These spectral indices are as low as 2-3, suggesting that grains in disks are much larger than those in the interstellar medium. In this study, we analyze the ALMA archival data of 23 disks in the Upper Scorpius region. The observed wavelength is 2.9 mm in Band 3, the angular resolution is 3<inline-formula><tex-math id="TM0001" notation="LaTeX">${_{.}^{\prime\prime}}$</tex-math></inline-formula>3 <inline-formula><tex-math id="TM0002" notation="LaTeX">$\times$</tex-math></inline-formula> 2<inline-formula><tex-math id="TM0003" notation="LaTeX">${_{.}^{\prime\prime}}$</tex-math></inline-formula>1, which is not high enough to resolve the targets, and the rms noise is below <inline-formula><tex-math id="TM0004" notation="LaTeX">$0.075~\mathrm{mJy}~\mathrm{beam}^{-1}$</tex-math></inline-formula> for almost all sources. Together with the literature values of the Band 7 fluxes of the same targets, we find that the average spectral index of the disks in the Upper Scorpius region is <inline-formula><tex-math id="TM0005" notation="LaTeX">$\alpha _\mathrm{mm}=2.09\pm 0.10$</tex-math></inline-formula>, which is equal to or slightly smaller than those in the other younger regions. To explain the relationship between the fluxes and spectral indices of the disks in the Taurus, Ophiuchus, Lupus, and Upper Scorpius regions, we construct simple disk evolution models. The observations are best reproduced by models in which the inner radius of the disk increases. This suggests that a substantial amount of dust mass must persist in the outer disk regions where the dust temperature is lower than 20 K even at late evolutionary stages. These findings offer key insights into the grain growth and the temporal evolution of protoplanetary disks.

We present the discovery of SN 2025wny (ZTF25abnjznp/GOTO25gqt) and spectroscopic classification of this event as the first gravitationally lensed Type I superluminous supernova (SLSN-I). Deep ground-based follow-up observations resolve four images of the supernova with <inline-formula> <mml:math><mml:mo>∼</mml:mo><mml:mn>1</mml:mn><mml:mover><mml:mrow><mml:mi>.</mml:mi></mml:mrow><mml:mrow><mml:mi>″</mml:mi></mml:mrow></mml:mover><mml:mn>7</mml:mn></mml:math> </inline-formula> angular separation from the main lens galaxy, each coincident with the lensed images of a background galaxy seen in archival imaging of the field. Spectroscopy of the brightest image shows narrow features matching absorption lines at a redshift of z = 2.010 and broad features matching those seen in superluminous SNe with far-UV coverage. We infer a magnification factor of μ ∼ 20─50 for the brightest image in the system, based on photometric and spectroscopic comparisons to other SLSNe-I. SN 2025wny demonstrates that gravitationally lensed SNe are in reach of ground-based facilities out to redshifts far higher than previously assumed, and provide a unique window into studying distant supernovae and the internal properties of dwarf galaxies, as well as for time-delay cosmography.

Time-delay cosmography leverages strongly lensed quasars to measure the Universe's current expansion rate, H_0, independently from other methods. While the latest TDCOSMO results relied mainly on quadruply lensed quasars, doubly lensed systems are far more common and offer precise time delays, potentially enlarging the usable sample by a factor of five and enabling percent-level constraints on H_0. We present the first TDCOSMO analysis of a doubly imaged source, HE1104-1805, including the measurement of the four necessary ingredients. First, by combining 17 years of data from the SMARTS, Euler and WFI telescopes, we measure a time delay of 176.3\pm 10.8 days. Second, using MUSE data, we extract stellar velocity dispersion measurements in three radial bins with up to 5% precision. Third, employing F160W HST imaging for lens modelling and marginalising over various modelling choices, we measure the Fermat potential difference between the images. Fourth, using wide-field imaging, we measure the convergence added by objects not included in the lens modelling. Hence, we measure the time delay distance and the angular diameter distance to the deflector, favouring a power-law mass model over a baryonic and dark matter composite model. The measurement was performed blindly and yielded H_0 = 64.2^{+5.8}_{-5.0} x $λ_{int} km s^{-1} Mpc^{-1}, where λ_{int} is the internal mass sheet degeneracy parameter. This is in agreement with the TDCOSMO-2025 milestone and its precision for λ_{int}=1 is comparable to that obtained with the best-observed quadruply lensed quasars (4-6%). This work is a stepping stone towards a precise measurement of H_0 using a large sample of doubly lensed quasars, supplementing the current sample. The next TDCOSMO milestone paper will include this system in its hierarchical analysis, constraining λ_{int} and H_0 jointly with multiple lenses.

We consider mixed strong-electroweak corrections to Higgs production via gluon fusion, in which the Higgs boson couples to the top quark. Using the method of differential equations, we compute all of the master integrals that contribute to this process at two loops through <inline-formula><mml:math><mml:mrow><mml:mi>O</mml:mi><mml:mo>(</mml:mo><mml:msup><mml:mrow><mml:mi>ϵ</mml:mi></mml:mrow><mml:mrow><mml:mn>2</mml:mn></mml:mrow></mml:msup><mml:mo>)</mml:mo></mml:mrow></mml:math></inline-formula> in the dimensional regularization parameter <inline-formula><mml:math><mml:mrow><mml:mi>ϵ</mml:mi><mml:mo>=</mml:mo><mml:mo>(</mml:mo><mml:mi>d</mml:mi><mml:mo>-</mml:mo><mml:mn>4</mml:mn><mml:mo>)</mml:mo><mml:mo>/</mml:mo><mml:mn>2</mml:mn></mml:mrow></mml:math></inline-formula>, keeping full analytic dependence on the top quark, Higgs, <inline-formula><mml:math><mml:mi>W</mml:mi></mml:math></inline-formula>, and <inline-formula><mml:math><mml:mi>Z</mml:mi></mml:math></inline-formula> boson masses. We present the results for these master integrals in terms of iterated integrals whose kernels depend on elliptic curves.

Neutrinos are the most abundant fundamental matter particles in the Universe and play a crucial part in particle physics and cosmology. Neutrino oscillation, discovered about 25 years ago, shows that the three known species mix with each other. Anomalous results from reactor and radioactive-source experiments¹ suggest a possible fourth neutrino state, the sterile neutrino, which does not interact through the weak force. The Karlsruhe Tritium Neutrino (KATRIN) experiment², primarily designed to measure the neutrino mass using tritium β-decay, also searches for sterile neutrinos suggested by these anomalies. A sterile-neutrino signal would appear as a distortion in the β-decay energy spectrum, characterized by a discontinuity in curvature (kink) related to the sterile-neutrino mass. This signature, which depends only on the shape of the spectrum rather than its absolute normalization, offers a robust, complementary approach to reactor experiments. Here we report the analysis of the energy spectrum of 36 million tritium β-decay electrons recorded in 259 measurement days within the last 40 eV below the endpoint. The results exclude a substantial part of the parameter space suggested by the gallium anomaly and challenge the Neutrino-4 claim. Together with other neutrino-disappearance experiments, KATRIN probes sterile-to-active mass splittings from a fraction of an eV² to several hundred eV², excluding light sterile neutrinos with mixing angles above a few per cent.

We study the cosmological gravitational particle production (CGPP) of spin-3/2 particles during and after cosmic inflation, and map the parameter space that can realize the observed dark matter density in stable spin-3/2 particles. Originally formulated by Rarita and Schwinger, the relativistic theory of a massive spin-3/2 field later found a home in supergravity as the superpartner of the graviton, and in nuclear physics as baryonic resonances and nuclear isotopes. We study a minimal model realization, namely a free massive spin-3/2 field minimally coupled to gravity, and adopt the name raritron for this field. We demonstrate that CGPP of raritrons crucially depends on the hierarchy between the raritron mass $m_{3/2}$ and the Hubble parameter at the end of inflation $H_e$, with high-mass and low-mass cases distinguished by the evolution of the sound speed $c_s$ of the longitudinal (helicity-1/2) mode, which is approximately unity at all times for heavy (relative to Hubble) raritrons and can become small or vanish for lighter raritrons, leading to a dramatic enhancement of production of high momentum particles in the latter case. Assuming the raritrons are stable, this leads to a wide parameter space to produce the observed dark matter density. Finally, we consider a time-dependent raritron mass, which can be chosen to remove the vanishing sound speed of the longitudinal mode, but which nonetheless enhances the production relative to the constant high-mass case, and in particular does not necessarily tame the high momentum tail of the spectrum. We perform our calculations using the Bogoliubov formalism and compare, when applicable, to the Boltzmann formalism.

Context. Accurately accounting for the Active Galactic Nucleus (AGN) phase in galaxy evolution requires a large, clean AGN sample. This is now possible with SRG/eROSITA, which completed its first all-sky X-ray survey (eRASS1) on June 12, 2020. The public Data Release 1 (DR1, Jan 31, 2024) includes 930,203 sources from the western Galactic hemisphere. Aims. The data enable the selection of a large AGN sample and the discovery of rare sources. However, scientific return depends on accurate characterisation of the X-ray emitters, requiring high-quality multi-wavelength data. This paper presents the identification and classification of optical and infrared counterparts to eRASS1 sources. Methods. Counterparts to eRASS1 X-ray point sources were identified using Gaia DR3, CatWISE2020, and Legacy Survey DR10 (LS10) with the Bayesian NWAY algorithm and trained priors. Sources were classified as Galactic or extragalactic via a machine-learning model combining optical/IR and X-ray properties, trained on a reference sample. For extragalactic LS10 sources, photometric redshifts were computed using CIRCLEZ. Results. Within the LS10 footprint, all 656,614 eROSITA/DR1 sources have at least one possible optical counterpart; ∼570 000 are extragalactic and likely AGN. Half are new detections compared to AllWISE, Gaia, and Quaia AGN catalogues. Gaia and CatWISE2020 counterparts are less reliable, due to the survey's shallowness and the limited amount of features available to assess the probability of being an X-ray emitter. In the Galactic plane, where the overdensity of stellar sources also increases the chance of associations, using conservative reliability cuts, we identified approximately 18 000 Gaia and 55 000 CatWISE2020 extragalactic sources. Conclusions. We have released three high-quality counterpart catalogues ─ plus the training and validation sets ─ as a benchmark for the field. These datasets have many applications, but in particular, they empower researchers to build AGN samples tailored for completeness and purity, accelerating the hunt for the Universe's most energetic engines.

We investigate the phases of a strongly coupled QCD-like theory at finite baryon chemical potential using s-confining supersymmetric QCD deformed by anomaly-mediated supersymmetry breaking. Focusing on the case of three colors and four flavors, we identify novel phases including spontaneous breaking of baryon number and/or parity. Both first-order and second-order phase transitions are observed as the baryon chemical potential is varied. These findings may offer insights into possible phases of real QCD at intermediate baryon densities.

Mock galaxy catalogues are often constructed from dark-matter-only simulations based on the galaxy-halo connection. Although modern mocks can reproduce galaxy clustering to some extent, the absence of baryons affects the spatial and kinematic distributions of galaxies in ways that remain insufficiently quantified. We compare the positions and velocities of satellite galaxies in the MTNG hydrodynamic simulation with those in its dark-matter-only counterpart, assessing how baryonic effects influence galaxy clustering and contrasting them with the impact of galaxy selection, i.e. the dependence of clustering on sample definition. Using merger trees from both runs, we track satellite subhaloes until they become centrals, allowing us to match systems even when their z=0 positions differ. We then compute positional and velocity offsets as functions of halo mass and distance from the halo centre, and use these to construct a subhalo catalogue from the dark-matter-only simulation that reproduces the galaxy distribution in the hydrodynamic run. Satellites in the hydrodynamic simulation lie 3-4% closer to halo centres than in the dark-matter-only case, with an offset that is nearly constant with halo mass and increases toward smaller radii. Satellite velocities are also systematically higher in the dark-matter-only run. At scales of 0.1 Mpc/h, these spatial and kinematic differences produce 10-20% variations in clustering amplitude -- corresponding to 1-3$σ$ assuming DESI-like errors -- though the impact decreases at larger scales. These baryonic effects are relevant for cosmological and lensing analyses and should be accounted for when building high-fidelity mocks. However, they remain smaller than the differences introduced by galaxy selection, which thus represents the dominant source of uncertainty when constructing mocks based on observable quantities.

Multiplanetary systems are excellent laboratories for studying the formation and evolution of exoplanets inside the same stellar environment. The number of known multiplanetary systems is expected to skyrocket with the advent of PLATO and the Roman space telescope. The spin-orbit angle is a key context information for the systems' dynamical history, and in recent years a growing number of planets had their spin-orbit angle measured, revealing a large diversity in orbital configurations, from well-aligned to polar, and even retrograde, orbits. Still, observers lack a robust tool to compare the dynamical state of different systems and to select the most suitable ones for future avenues of exploration, such as investigating the evolutionary pathways and their links to the atmospheric composition. Here, we present ExoNAMD, an open source code aimed at evaluating the dynamical state of multiplanetary systems via the Normalized Angular Momentum Deficit (NAMD) metric. The NAMD measures the deficit in angular momentum with respect to circular, co-planar orbits. It is normalized to compare systems with different architectures and provides a lower limit on the past dynamical excitation of the system. We find that using the spin-orbit angle parameter in the NAMD calculation (A-NAMD) improves the dynamical state's description, compared to using only the relative inclinations (R-NAMD). Comparison of A-NAMD and R-NAMD also yields powerful insights into the interplay between eccentricity and spin-orbit angle. ExoNAMD is a timely tool for easy and fast comparison of the myriad of exoplanetary systems to be discovered by PLATO and Roman, and to optimize the target selection and scientific output for future atmospheric characterization using ELTs, JWST, and Ariel.

The integration of aerodynamic drag is a fundamental step in simulating dust dynamics in hydrodynamical simulations. We propose a novel integration scheme, designed to be compatible with Strang splitting techniques, which allows for the straightforward integration of external forces and hydrodynamic fluxes in general-purpose hydrodynamic simulation codes. Moreover, this solver leverages an analytical solution to the problem of drag acceleration, ensuring linear complexity even in cases with multiple dust grain sizes, as opposed to the cubic scaling of methods that require a matrix inversion step. This new general implicit Runge─Kutta (GIRK) integrator is evaluated using standard benchmarks for dust dynamics such as DUSTYBOX, DUSTYWAVE, and DUSTYSHOCK. The results demonstrate not only the accuracy of the method but also the expected scalings in terms of accuracy, convergence to equilibrium, and execution time. GIRK can be easily implemented in hydrodynamical simulations alongside hydrodynamical steps and external forces and is especially useful in simulations with a large number of dust grain sizes.

We investigate dynamical symmetry breaking in a class of chiral gauge theories containing the Georgi-Glashow model. These theories feature a gauge sector and two fermion species that transform in the two-index antisymmetric and antifundamental representations with different multiplicities. Using the effective action formalism and the functional renormalization group, we derive the flow of four-fermion interactions that encode their resonant structure and information about bound-state formation. Generalizing the theories to multiple generations, we make contact with the loss of asymptotic freedom and dissect the boundary of a conjectured conformal window. Our results show that, while most of the theory space displays a dominant color-breaking condensate, there exists a strongly coupled regime where the lowest-laying mechanisms fail and more intricate dynamics are expected to arise. This analysis provides a first step toward the infrared behavior of chiral gauge theories with functional methods.

On 2025 August 18, the LIGO─Virgo─KAGRA collaboration reported gravitational waves from a subthreshold binary neutron star merger. If astrophysical, this event would have a surprisingly low chirp mass, suggesting that at least one neutron star was below a solar mass. The Zwicky Transient Facility mapped the coarse localization and discovered a transient, ZTF 25abjmnps (AT2025ulz), which was spatially and temporally coincident with the gravitational-wave trigger. The first week of follow-up suggested properties reminiscent of a GW170817-like kilonova. Subsequent follow-up suggests properties most similar to a young, stripped-envelope, Type IIb supernova. Although we cannot statistically rule out chance coincidence, we undertake due diligence analysis to explore the possible association between ZTF 25abjmnps and S250818k. Theoretical models have been proposed wherein subsolar neutron star(s) may form (and subsequently merge) via accretion-disk fragmentation or core fission inside a core-collapse supernova—i.e., a "superkilonova." Here, we qualitatively discuss our multiwavelength dataset in the context of the superkilonova picture. Future higher-significance gravitational-wave detections of subsolar neutron star mergers with extensive electromagnetic follow-up would conclusively resolve this tantalizing multimessenger association.

Context. Our picture of galaxy evolution currently assumes that galaxies spend their life on the star formation main sequence (SFMS) until they are eventually quenched. However, recent observations show indications that the full picture might be more complicated. Aims. We reveal typical in-situ star formation histories and their relations to large-scale environment as well as gas accretion across cosmic time. We further discuss systematic imprints on stellar masses, ages, and metallicities. Methods. We follow the evolution of central galaxies in the highest-resolution box of the MAGNETICUM PATHFINDER cosmological hydrodynamical simulations and classify their evolution scenarios with respect to the SFMS. Results. We find that a major fraction of the galaxies undergoes long-term cycles of quenching and rejuvenation on gigayear timescales. This expands the framework of galaxy evolution from a secular evolution to a sequence of multiple active and passive phases. Only 14% of field galaxies on the SFMS at z ≍ 0 actually evolved along the scaling relation, while the bulk of star-forming galaxies in the local Universe have undergone cycles of quenching and rejuvenation. In this work we describe the statistics of these galaxy evolution modes and how this impacts their mean stellar masses, ages, and metallicities today. We further explore possible explanations and find that the geometry of gas accretion at the halo outskirts shows a strong correlation with the star formation rate evolution, while the density parameter as a tracer of environment shows no significant correlation. A derivation of star formation rates from gas accretion with simple assumptions only works reasonably well in the high-redshift universe, where accreted gas is quickly converted into stars. Conclusions. We conclude that an evolution scenario consistently on the main sequence is the exception, when regarding galaxies on the main sequence at lower redshifts. Galaxies with rejuvenation cycles can be distinguished well from main-sequence-evolved galaxies, both in their halo accretion modes and in their features at z ≍ 0.

Active Galactic Nucleus (AGN) jets are thought to be vital ingredients in galaxy evolution through the action of kinetic feedback; however, how narrow, relativistic outflows couple to galaxies remains an open question. Jet deceleration, which is often attributed to the entrainment of material, such as stellar winds, is thought to be necessary for efficient coupling. We present a simple model of jet deceleration due to stellar mass-loading to investigate the energy budget of direct jet feedback in the local Universe. To this end, we produce models of stellar mass loss, including deriving a prescription for main-sequence mass-loss rates as a function of stellar population age. We pair this mass-loss data with a parametric fit for radio AGN incidence, predicting that a majority of jets are decelerated within their hosts, and generally replicate the expected FR-II fraction in LERGs. We calculate that ≳25% of the jet power in the local Universe is efficiently decelerated and available for direct feedback within galaxies for any stellar population age. This fraction is largely invariant to the shape of the radio AGN incidence function at low jet Eddington fractions. The stellar mass-loss rate evolves significantly over time, approximately following τ^−1.1, leading to corresponding decreases in decelerated jet power in older stellar populations. Although asymptotic giant branch stars dominate mass loss at all ages, we find that their stochasticity is important in low-mass galaxies, and derive a critical jet power below which main-sequence stars alone are sufficient to decelerate the jet.

We present constraints on the normal branch of the Dvali-Gabadadze-Porrati (nDGP) braneworld gravity model from the abundance of massive galaxy clusters. On scales below the nDGP crossover scale $r_{\rm c}$, the nDGP model features an effective gravity-like fifth force that alters the growth of structure, leading to an enhancement of the halo mass function (HMF) on cluster scales. The enhanced cluster abundance allows for constraints on the nDGP model using cluster samples. We employ the SPT cluster sample, selected through the thermal Sunyaev-Zel'dovich effect (tSZE) with the South Pole Telescope (SPT) and with mass calibration using weak-lensing data from the Dark Energy Survey (DES) and the Hubble Space Telescope (HST). The cluster sample contains 1,005 clusters with redshifts $0.25 < z < 1.78$, which are confirmed with the Multi-Component Matched Filter (MCMF) algorithm using optical and near-infrared data. Weak-lensing data from DES and HST enable a robust mass measurement of the cluster sample. We use DES Year 3 data for 688 clusters with redshifts $z < 0.95$, and HST data for 39 clusters with redshifts $ 0.6 < z <1.7$. We account for the enhancement in the HMF through a semi-analytic correction factor to the $νΛ$CDM HMF derived from the spherical collapse model in the nDGP model. We then further calibrate this model using $N$-body simulations. In addition, for the first time, we analyze the primary cosmic microwave background (CMB) temperature and polarization anisotropy measurements from Planck PR4 within the nDGP model. We obtain a competitive constraint from the joint analysis of the SPT cluster abundance with the Planck PR4 data, and report an upper bound of $1/\sqrt{H_0r_{\rm c}}< 1.41$ at $95\%$ when assuming a cosmology with massive neutrinos.

We analyze entanglement generated by the Schwinger effect using a mode-by-mode formalism for scalar and spinor QED in constant backgrounds. Starting from thermal initial states, we derive compact, closed-form results for bipartite entanglement between particle-antiparticle partners in terms of the Bogoliubov coefficients. For bosons, thermal fluctuations enhance production but suppress quantum correlations: the logarithmic negativity is nonzero only below a (mode-dependent) critical temperature $T_c$. At fixed $T$, entanglement appears only above a critical field $E_{\text{crit,entang}}$. For fermions, we observe a qualitatively different pattern: at finite $T$ entanglement exists only within a finite window $E_{\text{min}} < E < E_{\text{max}}$, with a temperature-independent optimal field strength $E_{*}$ that maximizes the logarithmic negativity. Entanglement is vanishing above $T_{\text{max}}=ω/\text{arcsinh}(1)$. We give quantitative estimates for analog experiments, where our entanglement criteria convert directly into concrete temperature and electric field constraints. These findings identify realistic regimes where the quantum character of Schwinger physics may be tested in the laboratory.

Ultracompact X-ray binaries (UCXBs) are a subclass of low-mass X-ray binaries characterized by tight orbits and degenerate donors, which pose significant challenges to our understanding of their formation. Recent discoveries of black hole (BH) candidates with main-sequence or red giant companions suggest that BH─white dwarf (BH─WD) binaries are common in the Galactic field. Motivated by these observations and the fact that most massive stars are born in triples, we show that wide BH─WD systems can naturally form UCXBs through the eccentric Kozai─Lidov (EKL) mechanism. Notably, EKL-driven eccentricity excitations combined with gravitational wave (GW) emission and WD dynamical tides can effectively shrink and circularize the orbit, leading to mass-transferring BH─WD binaries. These systems represent promising multimessenger sources in both X-ray and GW observations. Specifically, we predict that the wide triple channel can produce ∼3─27 (∼1─5) detectable UCXBs in the Milky Way (Andromeda galaxy), including ∼1 system observable by the mHz GW detection of LISA. If the final WD mass can reach sufficiently small values, this channel could contribute up to ∼10³ UCXBs in the Galaxy. Furthermore, the identification of tertiary companions in observed UCXBs would provide direct evidence for this formation pathway and yield unique insights into their dynamical origins.

We compute the primary Lund plane density for jets initiated by a massive ($b$) quark to single logarithmic accuracy in Quantum Chromodynamics (QCD). In order to capture mass effects, we consider quasi-collinear factorisation and we include contributions from the running of the QCD coupling and from collinear evolution, in a variable flavour-number scheme. Furthermore, the resummation of soft logarithms, including clustering effects, is performed numerically, keeping the full dependence on the $b$-quark mass. While our all-order results can be applied to both hadron and lepton colliders, we present, as first phenomenological application, the resummed calculation of the Lund plane density in $e^+e^-$ collisions at $\sqrt{s}=M_Z$, matched to tree-level matrix elements.

Blue supergiant distances of nearby galaxies obtained with the flux-weighted gravity─luminosity relationship are used for a measurement of the zero-points of Tully─Fisher relationships at different photometric passbands. The Cousins I band and the infrared WISE bands W1 and W2 are investigated. The results are compared with previous work using Cepheid and tip of the red giant branch distances. No significant differences were encountered. This supports the large values of the Hubble constant greater than 73 km s⁻¹ Mpc⁻¹ found with the Tully─Fisher distance ladder work over the last decade. Applying blue supergiant distances on the I-band Tully─Fisher relation observations yields a Hubble constant H₀ = 76.2 ± 6.2 km s⁻¹ Mpc⁻¹. The large uncertainty is caused by the still relatively small blue supergiant galaxy sample size but will be reduced in future work.

Ground-based high-resolution spectroscopy has identified various chemical species in the atmospheres of ultra-hot Jupiters, including neutral and ionized metals, providing key insights into planet formation through refractory element abundances. We observed the dayside thermal emission spectrum of the UHJ HAT-P-70b using the high-resolution spectrographs CARMENES and PEPSI. Through cross-correlation analysis, we detect emission signals of Al i, AlH, Ca ii, Cr i, Fe i, Fe ii, Mg i, Mn i, and Ti i, marking the first detection of Al i and AlH in an exoplanetary atmosphere. Tentative signals of C i, Ca i, Na i, NaH, and Ni i are also identified. These detections enable atmospheric retrievals to constrain the thermal profile and elemental abundances of the planet's dayside hemisphere. The retrieved temperature-pressure profile reveals a strong thermal inversion. The chemical free retrieval yields a metallicity of [Fe/H] = 0.38(+0.74/-1.11), while the chemical equilibrium retrieval gives [Fe/H] = 0.23(+1.08/-0.98), both consistent with solar metallicity. We also tentatively find an enhanced abundance of Ni, possibly due to the accretion of Ni-rich planetesimals during formation. On the other hand, elements with condensation temperatures above 1400 K (e.g., Ca, Ti, and V) appear slightly depleted, which may be caused by nightside cold trapping. However, Al, with the highest condensation temperature at 1653K, displays a solar like abundance, which might reflect the formation-related enrichment of Al. Our retrieval indicates extremely high volume mixing ratios of metal ions (Fe ii and Ca ii), which are significantly inconsistent with predictions from chemical equilibrium models. This disequilibrium suggests that the atmosphere is likely undergoing significant hydrodynamic escaping, which enhances the atmospheric density at high altitudes where the ionic lines are formed.

The relation between the masses of supermassive black holes (SMBHs) and their host galaxies encodes information on their mode of growth, especially at the earliest epochs. The James Webb Space Telescope (JWST) has opened such investigations by detecting the host galaxies of active galactic nuclei (AGN) and more luminous quasars within the first billion years of the Universe (z ≳ 6). Here, we evaluate the relation between the mass of SMBHs and the total stellar mass of their host galaxies using a sample of nine quasars at 6.18 ≤ z ≤ 6.4 from the Subaru High-z Exploration of Low-luminosity Quasars survey with NIRCam and NIRSpec observations. We find that the observed location of these quasars in the SMBH─galaxy mass plane (<inline-formula> <mml:math><mml:mi>log</mml:mi><mml:msub><mml:mi>M</mml:mi><mml:mi>BH</mml:mi></mml:msub><mml:mo>/</mml:mo><mml:msub><mml:mi>M</mml:mi><mml:mo>⊙</mml:mo></mml:msub><mml:mo>∼</mml:mo><mml:mn>8</mml:mn></mml:math> </inline-formula>─9; <inline-formula> <mml:math><mml:mi>log</mml:mi><mml:msub><mml:mi>M</mml:mi><mml:mo>*</mml:mo></mml:msub><mml:mo>/</mml:mo><mml:msub><mml:mi>M</mml:mi><mml:mo>⊙</mml:mo></mml:msub><mml:mo>∼</mml:mo><mml:mn>9.5</mml:mn></mml:math> </inline-formula>─11) is consistent with a nonevolving intrinsic mass relation with dispersion (<inline-formula> <mml:math><mml:mn>0.8</mml:mn><mml:msubsup><mml:mrow><mml:mn>0</mml:mn></mml:mrow><mml:mrow><mml:mo>−</mml:mo><mml:mn>0.28</mml:mn></mml:mrow><mml:mrow><mml:mo>+</mml:mo><mml:mn>0.23</mml:mn></mml:mrow></mml:msubsup></mml:math> </inline-formula> dex) higher than the local value (∼0.3─0.4 dex) of their more massive descendants. Our analysis is based on a forward model of systematics and includes a consideration of the impact of selection effects and measurement uncertainties with an assumption on the slope of the mass relation. While degeneracies between parameters persist, the best-fit solution has a reasonable AGN fraction (2.3%) of galaxies at z ∼ 6 with an actively growing UV-unobscured black hole. In particular, models with a substantially higher normalisation in M_BH would require an unrealistically low intrinsic dispersion (∼0.22 dex). Consequently, our results predict a large population of AGN at lower black hole masses, as are now just starting to be discovered in focused efforts with JWST.

Origins of life research investigates how life could emerge from prebiotic chemistry only. One possible explanation provides the RNA world hypothesis. It states that life could emerge from RNA strands only, storing and transferring biological information, as well as catalyzing reactions as ribozymes. Before this state could have emerged, however, the prebiotic world was probably a purely chemical pool of short RNA strands with random sequences and without biological function performing hybridization and dehybridization, as well as ligation and cleavage. In this context relevant questions are what are the conditions that allow longer RNA strands to be built and how can information carrying in RNA sequence emerge? In order to investigate such RNA reactors, efficient simulations are needed because the space of possible RNA sequences increases exponentially with the length of the strands, as well as the number of reactions between two strands. In addition, simulations have to be compared to experimental data for validation and parameter calibration. Here, we present the MoRSAIK python package for sequence motif (or k-mer) reactor simulation, analysis and inference. It enables users to simulate RNA sequence motif dynamics in the mean field approximation as well as to infer the reaction parameters from data with Bayesian methods and to analyze results by computing observables and plotting. MoRSAIK simulates an RNA reactor by following the reactions and the concentrations of all strands inside up to a certain length (of four nucleotides by default). Longer strands are followed indirectly, by tracking the concentrations of their containing sequence motifs of that maximum length.

Cosmology from weak gravitational lensing has been limited by astrophysical uncertainties in baryonic feedback and intrinsic alignments. By calibrating these effects using external data, we recover non-linear information, achieving a 2% constraint on the clustering amplitude, $S_8$, resulting in a factor of two improvement on the $Λ$CDM constraints relative to the fiducial Dark Energy Survey Year 3 model. The posterior, $S_8=0.832^{+0.013}_{-0.017}$, shifts by $1.5σ$ to higher values, in closer agreement with the cosmic microwave background result for the standard six-parameter $Λ$CDM cosmology. Our approach uses a star-forming 'blue' galaxy sample with intrinsic alignment model parameters calibrated by direct spectroscopic measurements, together with a baryonic feedback model informed by observations of X-ray gas fractions and kinematic Sunyaev-Zel'dovich effect profiles that span a wide range in halo mass and redshift. Our results provide a blueprint for next-generation surveys: leveraging galaxy properties to control intrinsic alignments and external gas probes to calibrate feedback, unlocking a substantial improvement in the precision of weak lensing surveys.

The dynamics of phase-separated interfaces shape the behavior of both passive and active condensates. While surface tension in equilibrium systems minimizes interface length, nonequilibrium fluxes can destabilize flat or constantly curved interfaces, giving rise to complex interface morphologies. Starting from a minimal model that couples a conserved, phase-separating species to a self-generated chemical field, we identify the conditions under which interfacial instabilities may emerge. Specifically, we show that nonreciprocal chemotactic interactions induce two distinct types of instabilities: a stationary (nonoscillatory) instability that promotes interface deformations and an oscillatory instability that can give rise to persistent capillary waves propagating along the boundaries of phase-separated domains. To characterize these phenomena, we develop a perturbative framework that predicts the onset, wavelength, and velocity of capillary waves, and quantitatively validate these predictions through numerical simulations. Beyond the linear regime, our simulations reveal that capillary waves undergo a secondary instability, leading to either stationary or dynamically evolving superpositions of different wave modes. Finally, we investigate whether capillary waves can facilitate directed mass transport, either along phase boundaries (conveyor belts) or through self-sustained liquid gears crawling along a solid wall. Taken together, our results establish a general framework for interfacial dynamics in active phase-separating systems and suggest strategies for controlling mass transport in soft matter and biological condensates.

Context. Dust dynamics plays a critical role in astrophysical processes and has been modeled in hydrodynamical simulations using various approaches. Among particle-based methods like Smoothed Particle Hydrodynamics (SPH), the One-Fluid model has proven to be highly effective for simulating gas-dust mixtures. Aims. This study presents the implementation of the One-Fluid model in OpenGadget3, introducing improvements to the original formulation. These enhancements include time-dependent artificial viscosity and conductivity, as well as a novel treatment of dust diffusion using a pressure-like term. Methods. The improved model is tested using a suite of dust dynamics benchmark problems: DUSTYBOX, DUSTYWAVE, and DUSTYSHOCK, with the latter extended to multidimensional scenarios, as well as a dusty Sedov-Taylor blast wave. Additional tests include simulations of Cold Keplerian Disks, dusty protoplanetary disks, and Kelvin─Helmholtz instabilities to evaluate the model's robustness in more complex flows. Results. The implementation successfully passes all standard benchmark tests. It demonstrates stability and accuracy in both simple and complex simulations. The new diffusion term improves the handling of flows with large dust-to-gas ratios and low drag coefficients, although limitations of the One-Fluid model in these regimes remain. Conclusions. The enhanced One-Fluid model is a reliable and robust tool for simulating dust dynamics in OpenGadget3. While it retains some limitations inherent to the original formulation, the introduced improvements expand its applicability and address some challenges in gas-dust dynamics.

Semi-classical dilaton gravity in (1+1)-dimensions remains one of the only arenas where quantum black holes can be exactly constructed, fully accounting for backreaction due to quantum matter. Here we provide a comprehensive analysis of the mass and thermodynamic properties of static asymptotically flat quantum black holes both analytically and numerically. First, we analytically investigate eternal quantum black hole solutions to a one-parameter family of analytically solvable models interpolating between Russo-Susskind-Thorlacius and Bose, Parker, and Peleg gravities. Examining these models in a semi-classically allowed parameter space, we find naked singularities may exist for quantum fields in the Boulware state. Using a quasi-local formalism, where we confine the black hole to a finite sized cavity, we derive the conserved energy and analyze the system's thermal behavior. Specifically, we show the semi-classical Wald entropy precisely equals the generalized entropy, accounting for both gravitational and fine grained matter entropies, and we find a range where the quantum black holes are thermally stable. Finally, we numerically construct eternal black hole solutions to semi-classical Callan-Giddings-Harvey-Strominger gravity and find their thermal behavior is qualitatively different from their analytic counterparts. In the process, we develop an analytic expansion of the solutions and find it accurately approximates the full numerical solutions in the semi-classical limit.

We present a very deep CO(3─2) observation of a massive, gas-rich, main sequence, barred spiral galaxy at z ≍ 1.52. Our data were taken with the IRAM-NOEMA interferometer for a 12-antenna equivalent on-source integration time of ∼50 hours. We fit the major axis kinematics with the forward modeling of a rotating disk and subtracted the two-dimensional beam convolved best-fit model, which revealed signatures of planar noncircular motions in the residuals. The inferred in-plane radial velocities are remarkably high, of the order of ≍60 km/s. Direct comparisons with a high-resolution, simulated, gas-rich, barred galaxy, obtained with the moving mesh code AREPO and the TNG sub-grid model, show that the observed noncircular gas flows can be explained as radial flows driven by the central bar, with an inferred net inflow rate of the order of the star formation rate (SFR). Given the recent evidence for a higher-than-expected fraction of barred disk galaxies at cosmic noon, our results suggest that rapid gas inflows due to bars could be important evolutionary drivers for the dominant population of star-forming galaxies at the peak epoch of star and galaxy formation.

GRB 250702B was the longest gamma-ray burst ever detected, with a duration that challenges standard collapsar models and suggests an exotic progenitor. We collected a rich set of optical and infrared follow-up observations of its rapidly fading afterglow using a suite of telescopes including the W. M. Keck Observatory, the Gemini telescopes, the Magellan Baade Telescope, the Victor M. Blanco 4 m telescope, and the Fraunhofer Telescope at Wendelstein Observatory. Our analysis reveals that the afterglow emission is well described by forward shock emission from a highly obscured relativistic jet. Deep photometric observations of the host galaxy reveal a massive (10^10.66 M_⊙), dusty, and extremely asymmetric system that is consistent with two galaxies undergoing a major merger. The galactocentric offset, host galaxy properties, and jet characteristics disfavor a jetted tidal disruption event (TDE) around a supermassive black hole but do not definitively distinguish between competing progenitor scenarios. We find that the afterglow and host are consistent with a range of progenitors, including an atypical collapsar, a merger between a helium star and a stellar-mass black hole, the disruption of a star by a stellar-mass compact object (micro-TDE), and the tidal disruption of a star by an off-nuclear intermediate-mass black hole.

We present the discovery of EP250827b/SN 2025wkm, an X-ray Flash (XRF) discovered by the Einstein Probe (EP), accompanied by a broad-line Type Ic supernova (SN Ic-BL) at $z = 0.1194$. EP250827b possesses a prompt X-ray luminosity of $\sim 10^{45} \, \rm{erg \, s^{-1}}$, lasts over 1000 seconds, and has a peak energy $E_{\rm{p}} < 1.5$ keV at 90% confidence. SN 2025wkm possesses a double-peaked light curve (LC), though its bolometric luminosity plateaus after its initial peak for $\sim 20$ days, giving evidence that a central engine is injecting additional energy into the explosion. Its spectrum transitions from a blue to red continuum with clear blueshifted Fe II and Si II broad absorption features, allowing for a SN Ic-BL classification. We do not detect any transient radio emission and rule out the existence of an on-axis, energetic jet $\gtrsim 10^{50}~$erg. In the model we invoke, the collapse gives rise to a long-lived magnetar, potentially surrounded by an accretion disk. Magnetically-driven winds from the magnetar and the disk mix together, and break out with a velocity $\sim 0.35c$ from an extended circumstellar medium with radius $\sim 10^{13}$ cm, generating X-ray breakout emission through free-free processes. The disk outflows and magnetar winds power blackbody emission as they cool, producing the first peak in the SN LC. The spin-down luminosity of the magnetar in combination with the radioactive decay of $^{56}$Ni produces the late-time SN LC. We end by discussing the landscape of XRF-SNe within the context of EP's recent discoveries.

Aims. Hyperluminous infrared galaxies (HyLIRGs; star-formation rates of up to ≍1000 M_⊙ yr⁻¹) ─ while rare ─ provide crucial long-lever-arm constraints on galaxy evolution. H-ATLAS J084933.4+021443, a z = 2.41 binary HyLIRG (galaxies 'W' and 'T') with at least two additional luminous companion galaxies ('C' and 'M'), is thus an optimal test ground for studies of star formation and galaxy evolution during 'cosmic noon'. Methods. We have used ALMA to obtain resolved imaging and kinematics of atomic and molecular emission lines, and rest-frame 340 to 1160 GHz continuum emission, for the galaxies W, T, M, and C. Results. All four galaxies are spatially resolved in CO J:7─6, [C I] 2─1, H₂O, and the millimetre (mm) to sub-millimetre continuum, using circular apertures of <inline-formula> ∼0.″3 <mml:math> <mml:mrow> <mml:mo>∼</mml:mo> <mml:mn>0</mml:mn> <mml:mover> <mml:mo>.</mml:mo> <mml:mo>″</mml:mo> </mml:mover> <mml:mn>3</mml:mn> </mml:mrow> </mml:math> </inline-formula> (2.5 kpc) in radius. Rotation-dominated gas kinematics are confirmed in W and T. The gas and continuum emission of galaxy T are extended along its kinematic minor axis, attributable to spatial lensing magnification. Spatially resolved sub-millimetre spectral energy distributions (SEDs) reveal that galaxy W is well fitted with greybody emission from dust at a single temperature over its full extent, despite hosting a powerful active galactic nucleus, while galaxy T requires an additional component of hotter nuclear dust and additional sources of emission in the millimetre. We confirm that [C I] J:2─1 can be used as a tracer of warm/dense molecular gas in extreme systems, though the [C I] J:2─1/CO J:7─6 luminosity ratio increases sub-linearly. We obtain an exquisite resolved (2.5-kpc-scale) Schmidt-Kennicutt (SK) relationship for galaxies W and T, using both cold and warm/dense molecular gas. Gas exhaustion timescales for all apertures in W (T) are ∼50─100 Myr (∼100─500 Myr). Both W and T follow a resolved SK relationship with a power-law index of n ∼ 1.7, significantly steeper than the n ∼ 1 found previously via cold molecular gas in nearby 'normal' star-forming galaxies.

We aim to study the atmospheric properties of the warm Neptune GJ 436 b by combining a set of five transit events observed with the CARMENES spectrograph with one transit from CRIRES$^+$ so as to provide the most constrained results possible at high resolution. We removed telluric and stellar signals from the data using SysRem and potential planetary signals were investigated using the cross-correlation technique. Following standard procedures for undetected species, we performed injection recovery tests and Bayesian retrievals to place constraints on the detectability of the main near-infrared absorbers. In addition, we simulated ELT/ANDES observations by computing end-to-end in silico datasets with EXoPLORE. No molecular signals were detected in the atmosphere of GJ 436 b, which is consistent with previous studies. Combined CARMENES-CRIRES$^+$ injection-recovery and Bayesian retrieval analyses show that the atmosphere is likely covered by high-altitude clouds ($\sim$ $1$ mbar) at low and intermediate metallicities or, alternatively, is very metal-rich ($\gtrsim$ $900\times$ solar), which would suppress spectral features without invoking clouds. Simulations of ELT/ANDES observations suggest a boost by nearly an order of magnitude to the upper limit in the photon-limited regime, reaching $0.1$ mbar at $10$-$300\times$ solar metallicities. The joint analysis of all useful transit observations from CARMENES and CRIRES$^+$ provides the most stringent constraints to date on the atmospheric properties of GJ 436 b. Complementary CCF-based and retrieval approaches consistently indicate that the atmosphere is either cloudy or highly metal enriched. Any weak near-infrared absorption lines, if present, are likely to be below current detection limits. However, according to our simulations, these features may be revealed with ELT/ANDES even in single-transit observations.

Luminous quasars at the redshift frontier z>7 serve as stringent probes of super-massive black hole formation and they are thought to undergo much of their growth obscured by dense gas and dust in their host galaxies. Fully characterizing the symbiotic evolution of SMBHs and hosts requires rest-frame optical observations that span spatial scales from the broad-line region to the ISM and CGM. JWST now provides the necessary spatially resolved spectroscopy to do so. But the physical conditions that regulate the interplay between SMBHs and their hosts at the highest redshifts, especially the nature of early feedback phases, remain unclear. We present JWST/NIRSpec IFU observations of J0313$-$1806 at z=7.64, the most distant luminous quasar known. From the restframe optical spectrum of the unresolved quasar, we derive a black hole mass of $M_\mathrm{BH}=(1.63 \pm 0.10)\times10^9 M_\odot$ based on H$β$ and an Eddington rate of $λ=L/L_\mathrm{Edd}=0.80\pm 0.05$, consistent with previous MgII-based estimates. J0313-1806 exhibits no detectable [O III] emission on nuclear scales. Most remarkably, we detect an ionized gas shell extending out to $\sim 1.8$ kpc traced by H$β$ emission that also lacks any significant [O III], with a $3σ$ upper limit on the [O III]$ λ$5007 to H$β$ flux ratio of $\log_{10} \left( F(\mathrm{[OIII]})/F(\mathrm{H}β)\right)=-1.15$. Through photoionization modelling, we demonstrate that the extended emission is consistent with a thin, clumpy outflowing shell where [OIII] is collisionally de-excited by dense gas. We interpret this structure as a fossil remnant of a recent blowout phase, providing evidence for episodic feedback cycles in one of the earliest quasars. These findings suggest that dense ISM phases may play a crucial role in shaping the spectral properties of quasars accross cosmic time.

We investigate the conditions under which the perturbative treatment of the backreaction of spin-2 particles on the dynamics of an axion-SU(2) gauge field system breaks down during cosmic inflation. This condition is based on the ratio of the energy density of spin-2 particles from the SU(2) gauge field to that of the background field. The perturbative treatment breaks down when this ratio exceeds unity. We show that this occurs within a parameter space nearly identical to the strong backreaction regime identified in previous studies. However, in some cases, the ratio exceeds unity even before the system enters the strong backreaction regime. Our results suggest that attempts to study the strong backreaction regime using perturbation theory are necessarily limited. Reliable calculations require non-perturbative treatments, such as three-dimensional lattice simulations.

Aims. We study the individual and cumulative impact of stellar feedback on massive black hole (MBH) growth in a simulated low-mass dwarf galaxy. Furthermore, we explore the influence of the MBH's initial mass (10³⁻⁶ M_⊙) on the gas accretion, and whether or not artificially induced gas inflows can 'boost' further gas accretion onto the MBH. Methods. A suite of high-resolution radiation-hydrodynamic simulations called NOCTUA were performed, using the AREPONOCTUA numerical framework. The chemical evolution of the interstellar medium (ISM) was modelled in a time-dependent non-equilibrium way. Two types of stellar feedback were considered: individually traced type II supernova (SNII) explosions, and radiatively transferred (on-the-fly) ionising stellar radiation (ISR) from OB stars. As part of AREPONOCTUA, we develop and apply a novel physically motivated model for MBH gas accretion, taking into account the angular momentum of the gas in the radiatively efficient regime, to estimate the gas accretion rate onto the MBH from its sub-grid accretion disc. Results. Without any stellar feedback, an initial 10⁴ M_⊙ MBH is able to steadily grow over time, roughly doubling its mass after 800 Myr. Surprisingly, the growth of the MBH more than doubles when only ISR feedback is considered, compared to the no stellar feedback run. This is due to the star formation rate (SFR) being highly suppressed (to a similar level or slightly above that when SNII feedback is considered), enabling a higher cumulative net gas inflow onto the MBH from not only the cold neutral and molecular medium phases, but also the unstable and warm neutral medium phases of the ISM. With SNII feedback included, the gas accretion onto the MBH is episodic over time, and is already suppressed by more than an order of magnitude during the first 150 Myr. When combining SNII with ISR feedback, the growth of the MBH remains suppressed due to SNII explosions, but to a lesser extent compared to the SNII-only feedback run, due to a slightly lower SFR, and thus a reduced number of SNII events. Conclusions. We conclude that SNII feedback is a strong regulator and suppressor of MBH growth, and that only an initial 10⁵ M_⊙ MBH is able to consistently accrete gas in the radiatively efficient regime (in the presence of SNII feedback). Combined with the fact that artificially induced gas inflows are unable to boost further gas accretion onto the MBH (even for an initial 10⁶ M_⊙ MBH), this suggests that it is primarily the nearby gravitational potential around the MBH that determines how much the MBH can grow via gas accretion over time (at least in an isolated non-cosmological environment).

Massive stars play a significant role in different branches of astronomy, from shaping the processes of star and planet formation to influencing the evolution and chemical enrichment of the distant universe. Despite their high astrophysical significance, these objects are rare and difficult to detect. With Gaia's advent, we now possess extensive kinematic and photometric data for a significant portion of the Galaxy that can unveil, among others, new populations of massive star candidates. In order to produce bonafide bright (G magnitude <12) massive-star candidate lists (threshold set to spectral type B2 or earlier but with slight changes in this threshold also explored) in the Milky Way subject to be followed up by future massive spectroscopic surveys, we developed a Gaia DR3 plus literature data based methodology. We trained a balanced random forest (BRF) with the spectral types from the Skiff compilation as labels. Our approach yields a completeness of ~80% and a purity ranging from 0.51 ± 0.02 for probabilities between 0.6 and 0.7, up to 0.85 ± 0.05 for the 0.9─1.0 range. To externally validate our methodology, we searched for and analyzed archival spectra of moderate- to high-probability (p > 0.6) candidates that are not contained in our catalog of labels. Our independent spectral validation confirms the expected performance of the BRF, spectroscopically classifying 300 stars as B3 or earlier (due to observational constraints imposed on the B0─3 range), including 107 new stars. Based on the most conservative yields of our methodology, our candidate list could increase the number of bright massive stars by ~50%. As a byproduct, we developed an automatic methodology for spectral typing optimized for LAMOST spectra, based on line detection and characterization that guides a decision path.

Modern radio interferometers deliver large volumes of data containing high-sensitivity sky maps over wide fields-of-view. These large area observations can contain various and superposed structures such as point sources, extended objects, and large-scale diffuse emission. To fully realize the potential of these observations, it is crucial to build appropriate sky emission models which separate and reconstruct the underlying astrophysical components. We introduce aim-resolve, an automatic and iterative method that combines the Bayesian imaging algorithm resolve with deep learning and clustering algorithms in order to jointly solve the reconstruction and source extraction problem. The method identifies and models different astrophysical components in radio observations while providing uncertainty quantification of the results. By using different model descriptions for point sources, extended objects, and diffuse background emission, the method efficiently separates the individual components and improves the overall reconstruction. We demonstrate the effectiveness of this method on synthetic image data containing multiple different sources. We further show the application of aim-resolve to an L-band (856 - 1712 MHz) MeerKAT observation of the radio galaxy ESO 137-006 and other radio galaxies in that environment. We observe a reasonable object identification for both applications, yielding a clean separation of the individual components and precise reconstructions of point sources and extended objects along with detailed uncertainty quantification. In particular, the method enables the creation of catalogs containing source positions and brightnesses and the corresponding uncertainties. The full decoupling of sky emission model and instrument response makes the method applicable to a wide variety of instruments or wavelength bands.

It has been suggested some time ago that many black hole properties are not specific to gravity, but rather are shared by a large class of objects, the so-called saturons, that saturate the quantum field theoretic upper bound on microstate degeneracy. By now, various aspects of this universality have been understood and demonstrated in a number of explicit examples. In the present paper, we add one more brick to the building by showing that the decay of a simple two-dimensional saturated soliton copies some key aspects of the black hole decay as well as of the information retrieval. In particular, we study the evaporation process of a classically stable vacuum bubble of a spontaneously broken <inline-formula><mml:math><mml:mi>S</mml:mi><mml:mi>U</mml:mi><mml:mo>(</mml:mo><mml:mi>N</mml:mi><mml:mo>)</mml:mo></mml:math></inline-formula>-symmetry, coupled to massless fermions. We show that the decay rate as well as the characteristic energy of the emitted quanta are given by the inverse size of the object, in striking similarity with the Hawking evaporation of a black hole. The timescale of information retrieval also matches the one previously suggested for a black hole by Page. We give the semiclassical derivation of the phenomenon as well as its fully quantum resolution as a decaying coherent state of Goldstone bosons. The universal nature of the effect and its microscopic understanding support the analogous quantum portrait of a black hole as a saturated coherent state of gravitons.

Intracellular protein patterns govern essential cellular functions by dynamically redistributing proteins between membrane-bound and cytosolic states, conserving their total numbers. This review presents a theoretical framework for understanding such patterns based on mass-conserving reaction--diffusion systems. The emergence, selection, and evolution of patterns are analyzed in terms of mass redistribution and interface motion, resulting in mesoscale laws of coarsening and wavelength selection. A geometric phase-space perspective provides a conceptual tool to link local reactive equilibria with global pattern dynamics through conserved mass fluxes. The Min protein system of \emph{Escherichia coli} provides a paradigmatic example, enabling direct comparison between theory and experiment. Successive model refinements capture both the robustness of pattern formation and the diversity of dynamic regimes observed \emph{in vivo} and \emph{in vitro}. The Min system thus illustrates how to extract predictive, multiscale theory from biochemical detail, providing a foundation for understanding pattern formation in more complex and synthetic systems.

Context. Disc winds driven by thermal and magnetic processes are thought to play a critical role in protoplanetary disc evolution. However, the relative contribution of each mechanism remains uncertain, particularly in light of their observational signatures. Aims. We investigate whether spatially resolved emission and synthetic spectral line profiles can be used to distinguish between thermally and magnetically driven winds in protoplanetary discs. Methods. We modelled three disc wind scenarios with different levels of magnetisation: a relatively strongly magnetised wind (β4), a rather weakly magnetised wind (β6), and a purely photoevaporative wind (PE). Using radiative transfer post-processing, we generated synthetic emission maps and line profiles for [OI] 6300 Å, [NeII] 12.81 μm, and o-H₂ 2.12 μm, and compared them with observational trends in the literature. Results. We find that the β4 model generally produces broader and more blueshifted low-velocity components across all tracers, consistent with compact emission regions and steep velocity gradients. The β6 and PE models yield narrower profiles with smaller blueshifts, in better agreement with most observed narrow low-velocity components (NLVCs). We also find that some line profile diagnostics, such as the inclination at maximum centroid velocity, are not robust discriminants. However, the overall blueshift and full width at half maximum of the low-velocity components provide reliable constraints. The β4 model reproduces the most extreme blueshifted NLVCs in observations, while most observed winds are more consistent with the β6 and PE models. Conclusions. Our findings reinforce previous conclusions that most observed NLVCs are compatible with weakly magnetised or purely photo-evaporative flows. The combination of line kinematics and emission morphology offers meaningful constraints on wind-driving physics, and synthetic line modelling remains a powerful tool for probing disc wind mechanisms.

Rocky planets orbiting M dwarf stars are prime targets for atmospheric characterization, yet their long-term evolution under intense stellar winds and high-energy radiation remains poorly constrained. The Kepler-1649 system, hosting two terrestrial exoplanets orbiting an M5V star, provides a valuable laboratory for studying atmospheric evolution in the extreme environments typical of M dwarf systems. In this Letter, we show that both planets could have retained atmospheres over gigayear timescales. Using a multispecies magnetohydrodynamic model, we simulate atmospheric ion escape driven by stellar winds and extreme-ultraviolet radiation from 0.8 to 4.0 Gyr. The results reveal a clear decline in total ion escape rates with stellar age, as captured by a nonparametric LOWESS regression, with O⁺ comprising 98.3%─99.9% of the total loss. Escape rates at 4.0 Gyr are 2 to 3 orders of magnitude lower than during early epochs. At 0.8 Gyr, planet b exhibits 3.79× higher O⁺ escape rates than planet c, whereas by 4.0 Gyr its O⁺ escape rates becomes 39.5× lower. This reversal arises from a transition to sub-magnetosonic star─planet interactions, where the fast magnetosonic Mach number, M_f, falls below unity. Despite substantial early atmospheric erosion, both planets may have retained significant atmospheres, suggesting potential long-term habitability. These findings offer predictive insight into atmospheric retention in the Kepler-1649 system and inform future JWST observations of similar M dwarf terrestrial exoplanets aimed at refining habitability assessments.

We develop a quadratic-in-Riemann worldline action for a Kerr black hole at infinite spin orders by matching to a proposed tree-level Kerr Compton amplitude, originally obtained from higher-spin QFT considerations. A worldline action is an effective theory, and as such the tree-level matching needs to be corrected by loop effects, including UV counter terms, renormalization, and higher-order matching to general relativity. However, we anticipate that many features of the Wilson coefficients of the proposed tree-level action will remain unchanged even after a loop-level matching. While the worldline action is given in closed form, it contains an infinite number of quadratic-in-Riemann operators $R^2$, even for the same-helicity sector. We argue that in the same-helicity sector the $R^2$ operators have no intrinsic meaning, as they merely remove unwanted terms produced by the linear-in-Riemann operators, which are well-established in the literature. The opposite-helicity sector is somewhat more complicated, it contains both $R^2$ operators that removes unwanted terms, and $R^2$ operators that add new needed terms to the Compton amplitude. We discuss and classify all independent $R^2$ operators that can feature in the worldline action.

Possible deformed neutron halos in silicon isotopes are investigated from both structure and reaction perspectives using the deformed relativistic Hartree-Bogoliubov theory in continuum (DRHBc) combined with the Glauber model. The experimental neutron separation energies of silicon isotopes are well reproduced by the DRHBc theory. Multiple halo criteria are examined, including the global ones based on root-mean-square radii and density profiles, as well as the microscopic ones based on single-particle orbitals and their spatial distributions. Calculations employing different density functionals and pairing strengths consistently indicate the emergence of $p$-wave neutron halos in $^{43,45}$Si, accompanied by pronounced shape decoupling between the halo and the core. Moreover, the enhanced reaction cross sections and the narrow longitudinal momentum distributions of one-neutron removal residues provide additional evidence supporting the halo structures in $^{43,45}$Si.

The hidden-charm pentaquark states <inline-formula><mml:math><mml:mrow><mml:msub><mml:mrow><mml:mi>P</mml:mi></mml:mrow><mml:mrow><mml:mi>c</mml:mi><mml:mover><mml:mrow><mml:mi>c</mml:mi></mml:mrow><mml:mrow><mml:mo>̄</mml:mo></mml:mrow></mml:mover></mml:mrow></mml:msub><mml:msup><mml:mrow><mml:mo>(</mml:mo><mml:mn>4312</mml:mn><mml:mo>)</mml:mo></mml:mrow><mml:mrow><mml:mo>+</mml:mo></mml:mrow></mml:msup></mml:mrow></mml:math></inline-formula>, <inline-formula><mml:math><mml:mrow><mml:msub><mml:mrow><mml:mi>P</mml:mi></mml:mrow><mml:mrow><mml:mi>c</mml:mi><mml:mover><mml:mrow><mml:mi>c</mml:mi></mml:mrow><mml:mrow><mml:mo>̄</mml:mo></mml:mrow></mml:mover></mml:mrow></mml:msub><mml:msup><mml:mrow><mml:mo>(</mml:mo><mml:mn>4380</mml:mn><mml:mo>)</mml:mo></mml:mrow><mml:mrow><mml:mo>+</mml:mo></mml:mrow></mml:msup></mml:mrow></mml:math></inline-formula>, <inline-formula><mml:math><mml:msub><mml:mi>P</mml:mi><mml:mrow><mml:mi>c</mml:mi><mml:mover><mml:mi>c</mml:mi><mml:mo>̄</mml:mo></mml:mover></mml:mrow></mml:msub><mml:msup><mml:mrow><mml:mo>(</mml:mo><mml:mn>4440</mml:mn><mml:mo>)</mml:mo></mml:mrow><mml:mo>+</mml:mo></mml:msup></mml:math></inline-formula>, and <inline-formula><mml:math><mml:msub><mml:mi>P</mml:mi><mml:mrow><mml:mi>c</mml:mi><mml:mover><mml:mi>c</mml:mi><mml:mo>̄</mml:mo></mml:mover></mml:mrow></mml:msub><mml:msup><mml:mrow><mml:mo>(</mml:mo><mml:mn>4457</mml:mn><mml:mo>)</mml:mo></mml:mrow><mml:mo>+</mml:mo></mml:msup></mml:math></inline-formula>, all with isospin <inline-formula><mml:math><mml:mi>I</mml:mi><mml:mo>=</mml:mo><mml:mn>1</mml:mn><mml:mo>/</mml:mo><mml:mn>2</mml:mn></mml:math></inline-formula>, were discovered by the LHCb Collaboration in the decay process <inline-formula><mml:math><mml:mrow><mml:msubsup><mml:mrow><mml:mi>Λ</mml:mi></mml:mrow><mml:mrow><mml:mi>b</mml:mi></mml:mrow><mml:mrow><mml:mn>0</mml:mn></mml:mrow></mml:msubsup><mml:mo>→</mml:mo><mml:mi>J</mml:mi><mml:mo>/</mml:mo><mml:mi>ψ</mml:mi><mml:mi>p</mml:mi><mml:msup><mml:mrow><mml:mi>K</mml:mi></mml:mrow><mml:mrow><mml:mo>-</mml:mo></mml:mrow></mml:msup></mml:mrow></mml:math></inline-formula>. Although their quantum numbers remain undetermined, these states have generated significant theoretical interest. We analyze their spectrum and decay patterns—including those of their spin partners—within the Born-Oppenheimer (BO) effective field theory (BOEFT), a framework grounded in QCD. At leading order in BOEFT, we identify these pentaquark states as bound states in BO potentials that exhibit at short distance a repulsive octet behavior and a nonperturbative shift due to the adjoint baryons masses, while asymptotically approaching the <inline-formula><mml:math><mml:msub><mml:mi>Σ</mml:mi><mml:mi>c</mml:mi></mml:msub><mml:mover><mml:mi>D</mml:mi><mml:mo>̄</mml:mo></mml:mover></mml:math></inline-formula> threshold. We further incorporate <inline-formula><mml:math><mml:mi>O</mml:mi><mml:mo>(</mml:mo><mml:mn>1</mml:mn><mml:mo>/</mml:mo><mml:msub><mml:mi>m</mml:mi><mml:mi>Q</mml:mi></mml:msub><mml:mo>)</mml:mo></mml:math></inline-formula> spin-dependent corrections to compute pentaquark multiplet spin splittings. Based on the spectrum, semi-inclusive decay widths to <inline-formula><mml:math><mml:mi>J</mml:mi><mml:mo>/</mml:mo><mml:mi>ψ</mml:mi></mml:math></inline-formula> and <inline-formula><mml:math><mml:msub><mml:mi>η</mml:mi><mml:mi>c</mml:mi></mml:msub></mml:math></inline-formula>, and the decay width ratios to <inline-formula><mml:math><mml:msub><mml:mi>Λ</mml:mi><mml:mi>c</mml:mi></mml:msub><mml:mover><mml:mi>D</mml:mi><mml:mo>̄</mml:mo></mml:mover></mml:math></inline-formula> and <inline-formula><mml:math><mml:msub><mml:mi>Λ</mml:mi><mml:mi>c</mml:mi></mml:msub><mml:msup><mml:mover><mml:mi>D</mml:mi><mml:mo>̄</mml:mo></mml:mover><mml:mo>*</mml:mo></mml:msup></mml:math></inline-formula>, we provide the first theoretical predictions for the adjoint baryon masses, which can be confirmed by future lattice QCD studies. Moreover, our analysis supports the quantum number assignments: <inline-formula><mml:math><mml:msup><mml:mi>J</mml:mi><mml:mi>P</mml:mi></mml:msup><mml:mo>=</mml:mo><mml:mo>(</mml:mo><mml:mn>1</mml:mn><mml:mo>/</mml:mo><mml:mn>2</mml:mn><mml:msup><mml:mo>)</mml:mo><mml:mo>-</mml:mo></mml:msup></mml:math></inline-formula> for <inline-formula><mml:math><mml:msub><mml:mi>P</mml:mi><mml:mrow><mml:mi>c</mml:mi><mml:mover><mml:mi>c</mml:mi><mml:mo>̄</mml:mo></mml:mover></mml:mrow></mml:msub><mml:msup><mml:mrow><mml:mo>(</mml:mo><mml:mn>4312</mml:mn><mml:mo>)</mml:mo></mml:mrow><mml:mo>+</mml:mo></mml:msup></mml:math></inline-formula>, <inline-formula><mml:math><mml:mo>(</mml:mo><mml:mn>3</mml:mn><mml:mo>/</mml:mo><mml:mn>2</mml:mn><mml:msup><mml:mo>)</mml:mo><mml:mo>-</mml:mo></mml:msup></mml:math></inline-formula> for <inline-formula><mml:math><mml:msub><mml:mi>P</mml:mi><mml:mrow><mml:mi>c</mml:mi><mml:mover><mml:mi>c</mml:mi><mml:mo>̄</mml:mo></mml:mover></mml:mrow></mml:msub><mml:msup><mml:mrow><mml:mo>(</mml:mo><mml:mn>4380</mml:mn><mml:mo>)</mml:mo></mml:mrow><mml:mo>+</mml:mo></mml:msup></mml:math></inline-formula>, <inline-formula><mml:math><mml:mo>(</mml:mo><mml:mn>1</mml:mn><mml:mo>/</mml:mo><mml:mn>2</mml:mn><mml:msup><mml:mo>)</mml:mo><mml:mo>-</mml:mo></mml:msup></mml:math></inline-formula> for <inline-formula><mml:math><mml:msub><mml:mi>P</mml:mi><mml:mrow><mml:mi>c</mml:mi><mml:mover><mml:mi>c</mml:mi><mml:mo>̄</mml:mo></mml:mover></mml:mrow></mml:msub><mml:msup><mml:mrow><mml:mo>(</mml:mo><mml:mn>4457</mml:mn><mml:mo>)</mml:mo></mml:mrow><mml:mo>+</mml:mo></mml:msup></mml:math></inline-formula>, and <inline-formula><mml:math><mml:mo>(</mml:mo><mml:mn>3</mml:mn><mml:mo>/</mml:mo><mml:mn>2</mml:mn><mml:msup><mml:mo>)</mml:mo><mml:mo>-</mml:mo></mml:msup></mml:math></inline-formula> for <inline-formula><mml:math><mml:msub><mml:mi>P</mml:mi><mml:mrow><mml:mi>c</mml:mi><mml:mover><mml:mi>c</mml:mi><mml:mo>̄</mml:mo></mml:mover></mml:mrow></mml:msub><mml:msup><mml:mrow><mml:mo>(</mml:mo><mml:mn>4440</mml:mn><mml:mo>)</mml:mo></mml:mrow><mml:mo>+</mml:mo></mml:msup></mml:math></inline-formula>. We also present results for the lowest bottom pentaquarks.

DESI DR2 data have been widely interpreted as evidence for late-time evolving dark energy (DE) with an apparent phantom crossing. Here we investigate an alternative explanation, based on early-Universe physics. If dark acoustic oscillations (DAO) are close in scale to baryon acoustic oscillations (BAO), they can bias the extraction of the BAO scale from the peak in the galaxy correlation function. This leads to an apparent shift in the inferred distance if the superposition of BAO and DAO features is misinterpreted as being due to BAO only. Taking this shift into account, we find that a DAO with percent-level amplitude can reconcile DESI DR2 with Planck 2018 as well as Pantheon+ supernovae data, with fit improvement at a similar level as compared to evolving DE. Notably, a DAO feature with the required properties has been predicted in a previously proposed scenario that resolves the Hubble tension via a pre-recombination decoupling of dark matter and dark radiation (DRMD). The presence of a DAO feature close to the BAO peak can be scrutinized with future full-shape galaxy clustering data from DESI and Euclid.

This White Paper outlines a coordinated, decade-spanning programme of hadron and QCD studies anchored at the GSI/FAIR accelerator complex. Profiting from intense deuteron, proton and pion beams coupled with high-rate capable detectors and an international theory effort, the initiative addresses fundamental questions related to the strong interaction featuring confinement and dynamical mass generation. This includes our understanding of hadron-hadron interactions and the composition of hadrons through mapping the baryon and meson spectra, including exotic states, and quantifying hadron structure. This interdisciplinary research connects topics in the fields of nuclear, heavy-ion, and (nuclear) astro (particle) physics, linking, for example, terrestrial data to constraints on neutron star structure. A phased roadmap with SIS100 accelerator start-up and envisaged detector upgrades will yield precision cross sections, transition form factors, in-medium spectral functions, and validated theory inputs. Synergies with external programmes at international accelerator facilities worldwide are anticipated. The programme is expected to deliver decisive advances in our understanding of non-perturbative (strong) QCD and astrophysics, and high-rate detector and data-science technology.

We present a cosmological zoom-in simulation targeting the high redshift compact progenitor phase of massive galaxies, with the most massive galaxy reaching a stellar mass of $M_{\star}=8.5\times 10^{10} \ M_{\odot}$ at $z=5$. The dynamics of supermassive black holes (SMBHs) is modelled from seeding down to their coalescence at sub-parsec scales due to gravitational wave (GW) emission by utilising a new version of the KETJU code, which combines regularised integration of sufficiently massive SMBHs with a dynamical friction subgrid model for lower-mass SMBHs. All nine massive galaxies included in this study go through a gas-dominated phase of early compaction in the redshift range of $z\sim 7-9$, starting at stellar masses of $M_\star\gtrsim 10^8\ \mathrm{M}_\odot$ and ending at a few times $M_{\star}\sim 10^9\ \mathrm{M}_\odot$. The sizes, masses and broad band fluxes of these compact systems are in general agreement with the population of systems observed with JWST known as `Little Red Dots'. In the compact phase, the stellar and SMBH masses grow rapidly, leading to a sharp decline in the central gas fractions. The outer regions, however, remain relatively gas-rich, leading to subsequent off-centre star formation and size growth. Due to the very high central stellar densities ($ρ_{\star}\gtrsim 10^{13}\,\mathrm{M_\odot/kpc^3}$), the SMBHs merge rapidly, typically just $\sim 4-35\ \mathrm{Myr}$ after the SMBH binaries have become bound. Combining KETJU with the phenomenological PhenomD model resolves the complete evolution of the GW emission from SMBH binaries through the Pulsar Timing Array frequency waveband up to the final few orbits that produce GWs observable with the future LISA mission.

Disc winds driven by thermal and magnetic processes are thought to play a critical role in protoplanetary disc evolution. However, the relative contribution of each mechanism remains uncertain, particularly in light of their observational signatures. We investigate whether spatially resolved emission and synthetic spectral line profiles can distinguish between thermally and magnetically driven winds in protoplanetary discs. We modelled three disc wind scenarios with different levels of magnetisation: a relatively strongly magnetised wind (β4), a rather weakly magnetised wind (β6), and a purely photoevaporative wind (PE). Using radiative transfer post-processing, we generated synthetic emission maps and line profiles for [OI] 6300 Å, [NeII] 12.81 μm, and o-H2 2.12 μm, and compared them with observations. The β4 model generally produces broader and more blueshifted low-velocity components across all tracers, consistent with compact emission regions and steep velocity gradients. The β6 and PE models yield narrower profiles with smaller blueshifts, in better agreement with most observed narrow low-velocity components (NLVCs). We also find that some line profile diagnostics, such as the inclination at maximum centroid velocity, are not robust discriminants. However, the overall blueshift and full-width at half-maximum (FWHM) of the low-velocity components provide reliable constraints. The β4 model reproduces the most extreme blueshifted NLVCs in observations, while most observed winds are more consistent with the β6 and PE models. Our findings reinforce previous conclusions that most observed NLVCs are compatible with weakly magnetised or purely photoevaporative flows. The combination of line kinematics and emission morphology offers meaningful constraints on wind-driving physics.

Neutron supermirrors are a crucial part of many scattering and particle physics experiments. So far, Ni(Mo)/Ti supermirrors have been used in experiments that require to transport a polarized neutron beam due to their lower saturation magnetization compared to Ni/Ti supermirrors. However, next generation <mml:math><mml:mi>β</mml:mi></mml:math> decay experiments require supermirrors that depolarize below <mml:math><mml:mrow><mml:mn>1</mml:mn><mml:msup><mml:mrow><mml:mn>0</mml:mn></mml:mrow><mml:mrow><mml:mo>‑</mml:mo><mml:mn>4</mml:mn></mml:mrow></mml:msup></mml:mrow></mml:math> per reflection to reach their targeted precision. The depolarization of a polarized neutron beam due to reflection off Ni(Mo)/Ti supermirrors has not yet been measured to that precision. Recently, Cu/Ti supermirrors with a lower saturation magnetization compared to Ni(Mo)/Ti have been developed, and may serve as an alternative. In this paper, we test the performance of both mirrors. At a first stage, we present four-states polarized neutron reflectivity curves of Ni(Mo) and Cu monolayers and <mml:math><mml:mrow><mml:mi>m</mml:mi><mml:mo>=</mml:mo><mml:mn>2</mml:mn></mml:mrow></mml:math> Ni(Mo)/Ti and Cu/Ti supermirrors measured at the neutron reflectometer SuperADAM and perform a full polarization analysis, with the aim to extract information about their magnetic moment. The results found, however, were inconclusive, since it seems a detection limit of this method for all measured samples was reached. At a second stage, we measured the depolarization (<mml:math><mml:mi>D</mml:mi></mml:math>) that a polarized neutron beam suffers after reflection off the same Ni(Mo)/Ti and Cu/Ti supermirrors by using the Opaque Test Bench setup. We find upper limits for the depolarization of <mml:math><mml:mrow><mml:msub><mml:mrow><mml:mi>D</mml:mi></mml:mrow><mml:mrow><mml:mtext>Cu/Ti(4N5)</mml:mtext></mml:mrow></mml:msub><mml:mo><</mml:mo><mml:mn>7</mml:mn><mml:mo>.</mml:mo><mml:mn>6</mml:mn><mml:mo>×</mml:mo><mml:mn>1</mml:mn><mml:msup><mml:mrow><mml:mn>0</mml:mn></mml:mrow><mml:mrow><mml:mo>‑</mml:mo><mml:mn>5</mml:mn></mml:mrow></mml:msup></mml:mrow></mml:math>, <mml:math><mml:mrow><mml:msub><mml:mrow><mml:mi>D</mml:mi></mml:mrow><mml:mrow><mml:mtext>Ni(Mo)/Ti</mml:mtext></mml:mrow></mml:msub><mml:mo><</mml:mo><mml:mn>8</mml:mn><mml:mo>.</mml:mo><mml:mn>5</mml:mn><mml:mo>×</mml:mo><mml:mn>1</mml:mn><mml:msup><mml:mrow><mml:mn>0</mml:mn></mml:mrow><mml:mrow><mml:mo>‑</mml:mo><mml:mn>5</mml:mn></mml:mrow></mml:msup></mml:mrow></mml:math>, and <mml:math><mml:mrow><mml:msub><mml:mrow><mml:mi>D</mml:mi></mml:mrow><mml:mrow><mml:mtext>Cu/Ti(2N6)</mml:mtext></mml:mrow></mml:msub><mml:mo><</mml:mo><mml:mn>6</mml:mn><mml:mo>.</mml:mo><mml:mn>0</mml:mn><mml:mo>×</mml:mo><mml:mn>1</mml:mn><mml:msup><mml:mrow><mml:mn>0</mml:mn></mml:mrow><mml:mrow><mml:mo>‑</mml:mo><mml:mn>5</mml:mn></mml:mrow></mml:msup></mml:mrow></mml:math> at the <mml:math><mml:mrow><mml:mn>1</mml:mn><mml:mi>σ</mml:mi></mml:mrow></mml:math> confidence level, where (4N5) corresponds to a Ti purity of <mml:math><mml:mrow><mml:mn>99</mml:mn><mml:mo>.</mml:mo><mml:mn>995</mml:mn><mml:mspace></mml:mspace><mml:mstyle><mml:mi>%</mml:mi></mml:mstyle></mml:mrow></mml:math> and (2N6) to <mml:math><mml:mrow><mml:mn>99</mml:mn><mml:mo>.</mml:mo><mml:mn>6</mml:mn><mml:mspace></mml:mspace><mml:mstyle><mml:mi>%</mml:mi></mml:mstyle></mml:mrow></mml:math>. These results show that all three supermirrors are suitable for being used in next generation <mml:math><mml:mi>β</mml:mi></mml:math> decay experiments. We found no noticeable dependence of the depolarization on the <mml:math><mml:mi>q</mml:mi></mml:math> value or the magnetizing field, in which the samples were placed.

Cosmic-ray physics in the GeV-to-TeV energy range has entered a precision era thanks to recent data from space-based experiments. However, the poor knowledge of nuclear reactions, in particular for the production of antimatter and secondary nuclei, limits the information that can be extracted from these data, such as source properties, transport in the Galaxy and indirect searches for particle dark matter. The Cross-Section for Cosmic Rays at CERN workshop series has addressed the challenges encountered in the interpretation of high-precision cosmic-ray data, with the goal of strengthening emergent synergies and taking advantage of the complementarity and know-how in different communities, from theoretical and experimental astroparticle physics to high-energy and nuclear physics. In this paper, we present the outcomes of the third edition of the workshop that took place in 2024. We present the current state of cosmic-ray experiments and their perspectives, and provide a detailed road map to close the most urgent gaps in cross-section data, in order to efficiently progress on many open physics cases, which are motivated in the paper. Finally, with the aim of being as exhaustive as possible, this report touches several other fields – such as cosmogenic studies, space radiation protection and hadrontherapy – where overlapping and specific new cross-section measurements, as well as nuclear code improvement and benchmarking efforts, are also needed. We also briefly highlight further synergies between astroparticle and high-energy physics on the question of cross-sections.

The combined use of the inverse kinematics technique and the advanced detection setup R³B (Reactions with Relativistic Radioactive Beams) at GSI/FAIR provides unique opportunities to study the fission process. This approach provides access to the complete isotopic identification of the two fission fragments, the precise determination of their velocities and the measurement of the neutrons and gammas emitted in coincidence, for a wide range of unstable fissile nuclei. In addition, quasi-free NN scattering represents a surrogate reaction to induce fission, allowing the complete identification of the fissioning system in terms of isotopic composition and excitation energy. The manuscript describes the technical realisation of these experiments as well as the physics programme and some preliminary results.

Dusty, submillimeter-selected galaxies without optical counterparts contribute a non-negligible fraction of the star formation in the early universe. However, such a population is difficult to detect through classical optical/UV-based surveys. We report the serendipitous discovery of such an optically dark galaxy, behind the quadruply-lensed $z=2.56$ quasar, H1413+117, offset to the north by 6\arcsec. From $^{12}$CO $J=4$--3, $J=6$--5, and part of the $J=13$--12 transitions, which all spatially coincide with a compact submillimeter continuum emission, we determine an unambiguous spectroscopic redshift, $z=3.386\pm 0.005$. This galaxy has a molecular mass $M_{\rm mol} \sim 10^{11}$ M$_\odot$ and a black hole mass $M_{\rm BH} \sim 10^{8}$ M$_\odot$, estimated from $^{12}$CO $J=4$--3 and archival {\it Chandra} X-ray data ($L_{\rm 2-10,keV} \sim 4 \times 10^{44}$\,erg\,s$^{-1}$), respectively. We also estimate a total infrared luminosity of $L_{\rm FIR} = (2.8\pm{2.3}) \times 10^{12}$ L$_\odot$ and a stellar mass of $M_* \lesssim 10^{11}$ M$_{\odot}$, from spectral energy distribution fitting. According to these simple mass estimations, this gas-rich and X-ray bright galaxy might be in a transition phase from starburst to quasar offering a unique case for studying galaxy-black hole co-evolution under extremely dusty conditions.

The diffuse supernova neutrino background (DSNB) created by stellar core-collapses throughout cosmic history is on the verge of discovery, with SK-Gd showing early deviations from the background expectation and JUNO starting to take data. However, the interpretation of early DSNB data will face significant challenges due to degeneracies between astrophysical parameters and uncertainties in supernova neutrino modeling. We explore how complementary astronomical observations can break these degeneracies and, in this context, we investigate whether early DSNB observations can constrain invisible supernovae, which have no optical emission but are powerful neutrino sources before being swallowed by a forming black hole. Leveraging the differences in the spectra between invisible and visible supernovae, we estimate the sensitivity of 1) detecting the existence of invisible supernovae, and 2) determining the fraction of invisible supernovae. Finally, we discuss how these conclusions depend on the spectral parameters of the black hole-forming component.

Polarimetry is a promising technique in astrophysics for studying compact objects such as black holes and neutron stars, whose structure cannot be resolve with current telescopes. Polarization measurements, including the degree and angle of polarization, can provide additional model constraints beyond spectral data. Cygnus X-1, a black hole binary and one of the brightest X-ray sources observable from Earth, is still not fully understood regarding its magnetic fields, accretion disk and corona structure, X-ray emission processes, and variable spectral states. This thesis presents the design of ComPol (Compton Polarimeter), an X-ray polarimeter aiming to observe Cygnus X-1 in the 20–200 keV energy range. Although the instrument is designed to fit within a nano-satellite, it has the potential to contribute valuable information about Cygnus X-1. The underlying measurement principle is based on the polarization-dependent cross section of Compton scattering. The detector system to capture the scattering kinematics for each event consists of two detector layers: a Silicon Drift Detector (SDD) to scatter the X-rays and a CeBr3 scintillator to absorb the scattered photons. A prototype module was developed and calibrated, including energy, position, and time coincidence calibration. Additional hardware characterization was conducted at the LARIX facility in Ferrara (Italy) with a monochromatic X-ray beam, enabling studies of sub-pixel performance of the SDD, non-linearities, and of the Compton cross section. Though no polarized beam was available, polarization analysis principles were also demonstrated. The last part of this thesis is dedicated to a sensitivity study of the final ComPol satellite instrument. The study considers realistic Cygnus X-1 and background spectra, the detector responses, and the satellites geometry. It allows to investigate data rates, angular resolutions, shielding and background effects, and the polarization sensitivity. The Minimum Detectable Polarization (MDP) is estimated at 16.9% after six months, with potential improvements lowering it below 10%, making ComPol competitive with current instruments. In summary, this work demonstrates the scientific potential and feasibility of a nano-satellite platform for X-ray polarimetry, while forming a foundation for the final ComPol instrument design.

We study ultralight scalar fields with quadratic couplings to Standard-Model fermions and derive strong constraints from white-dwarf mass-radius data. Such couplings source scalar profiles inside compact stars, shift fermion masses, and can produce a new ground state of matter. We analyze couplings to electrons and to nucleons, incorporating composition and finite-temperature effects in white dwarf structure and equations of state. We identify two robust observables: (i) forbidden gaps - ranges of radii with no stable configurations - and (ii) characteristic shape distortions that drive white dwarf masses toward the Chandrasekhar limit (electron couplings) or shift the maximum mass (nucleon couplings). Confronting these predictions with precise measurements for Sirius B and Procyon B, together with the global white dwarf population, excludes large regions of unexplored parameter space and extends earlier QCD-axion-specific bounds to a broader class of scalar theories. Our stellar constraints rely only on sourcing and do not assume the scalar constitutes dark matter; where mass reductions are small, precision laboratory searches remain competitive. White-dwarf astrophysics thus provides a powerful, largely assumption-minimal probe of ultralight, quadratically coupled scalars.

Cross-correlations techniques offer an alternative method to search for molecular species in JWST observations of exoplanet atmospheres. In a previous article, we applied cross-correlation functions for the first time to JWST NIRSpec/G395H observations of exoplanet atmospheres, resulting in a detection of CO in the transmission spectrum of WASP-39b and a tentative detection of CO isotopologues. Here we present an improved version of our cross-correlation technique and an investigation into how efficient the technique is when searching for other molecules in JWST NIRSpec/G395H data. Our search results in the detection of more molecules via cross-correlations in the atmosphere of WASP-39b, including $\rm H_{2}O$ and $\rm CO_{2}$, and confirms the CO detection. This result proves that cross-correlations are a robust and computationally cheap alternative method to search for molecular species in transmission spectra observed with JWST. We also searched for other molecules ($\rm CH_{4}$, $\rm NH_{3}$, $\rm SO_{2}$, $\rm N_{2}O$, $\rm H_{2}S$, $\rm PH_{3}$, $\rm O_{3}$ and $\rm C_{2}H_{2}$) that were not detected, for which we provide the definition of their cross-correlation baselines for future searches of those molecules in other targets. We find that that the cross-correlation search of each molecule is more efficient over limited wavelength regions of the spectrum, where the signal for that molecule dominates over other molecules, than over broad wavelength ranges. In general we also find that Gaussian normalization is the most efficient normalization mode for the generation of the molecular templates.

Multiple photometric studies have reported the presence of seemingly older accreting pre-main sequence stars (PMS) in optical colour-magnitude diagrams (CMDs). We investigate this phenomenon in the Orion Nebula, which harbors a subset of stars that show infrared excess detected by Spitzer and Halpha excess emission, yet display significantly older isochronal ages (>10 Myr) compared to the bulk population (~1-3 Myr) in the r, (r-i) CMD. We perform a detailed spectroscopic analysis of 40 Orion Nebula stars using VLT/X-Shooter, covering CMD-based isochronal ages from 1 to over 30 Myr. We derive extinction values, stellar properties, and accretion parameters by modeling the ultraviolet excess emission through a multicomponent fitting procedure. The sample spans spectral types from M4.5 up to K6, and masses in the range ~0.1-0.8 Msun. We demonstrate that, when extinction and, most importantly, accretion effects are accurately constrained, the stellar luminosity and effective temperature of the majority of the seemingly old stars become consistent with a younger population (~1-5 Myr). This is supported by strong lithium absorption, which corroborates their youth, and by the accretion-to-stellar luminosity ratios typical for young, accreting stars. Three of these sources, however, remain old even after our analysis, despite showing signatures consistent with ongoing accretion from a protoplanetary disc. More generally, our analysis indicates that excess continuum emission from accretion shocks affects the placement of PMS stars in the CMD, displacing sources towards bluer optical colours. This study highlights the critical role of accretion in shaping the stellar properties estimates (including age) derived from optical CMDs and emphasizes the need to carefully account for accretion effects when interpreting age distributions in star-forming regions.

Active galactic nuclei (AGN) emit radiation via accretion across the entire energy spectrum. While the standard disk and corona model can somewhat describe this emission, it fails to predict specific features such as the soft X-ray excess, the short-term optical/UV variability, and the observed UV/X-ray correlation in AGN. In this context, the fraction of AGN emission in different bands (i.e., bolometric corrections) can be useful to better understand the accretion physics of AGN. Past studies have shown that the X-ray bolometric corrections are strongly dependent on the physical properties of AGN, such as their luminosities and Eddington ratios. However, since these two parameters depend on each other, it has been unclear which is the main driver of the X-ray bolometric corrections. We present here results from a large study of hard-X-ray-selected (14–195 keV) nearby (z < 0.1) AGN. Based on our systematic analysis of the simultaneous optical-to-X-ray spectral energy distributions of 236 unobscured AGN, we found that the primary parameter controlling the X-ray bolometric corrections is the Eddington ratio. Our results show that, while the X-ray bolometric correction increases with the bolometric luminosity for sources with intermediate Eddington ratios (0.01–1), this dependence vanishes for sources with lower Eddington ratios (<0.01). This could be used as evidence for a change in the accretion physics of AGN at low Eddington ratios.

Multiply-imaged supernovae (SNe) provide a novel means of constraining the Hubble constant ($H_0$). Such measurements require a combination of precise models of the lensing mass distribution and an accurate estimate of the relative time delays between arrival of the multiple images. Only two multiply-imaged SNe, Refsdal and H0pe, have enabled measurements of $H_0$ thus far. Here we detail the third such measurement for SN Encore, a $z=1.95$ SNIa discovered in JWST/NIRCam imaging. We measure the time delay, perform simulations of additional microlensing and millilensing systematics, and combine with the mass models of Suyu et al. in a double-blind analysis to obtain our $H_0$ constraint. Our final time-delay measurement is $Δt_{1b,1a}=-39.8_{-3.3}^{+3.9}$ days, which is combined with seven lens models weighted by the likelihood of the observed multiple image positions for a result of $H_0=66.9_{-8.1}^{+11.2} \rm{km} \rm{s}^{-1}\rm{Mpc}^{-1}$. The uncertainty on this measurement could be improved significantly if template imaging is obtained. Remarkably, a sibling to SN Encore (SN "Requiem") was discovered in the same host galaxy, making the MACS J0138.0-2155 cluster the first system known to produce more than one observed multiply-imaged SN. SN Requiem has a fourth image that is expected to appear within a few years, providing an unprecedented decade-long baseline for time-delay cosmography and an opportunity for a high-precision joint estimate of $H_0$.

Earthshine observations offer a unique opportunity to study Earth as an exoplanet seen from the Moon. As the Sun-Earth-Moon geometry changes, Earth can be observed as a spatially unresolved exoplanet at different phase angles, providing important context for future observations of Earth-like exoplanets. Here, we present a catalog of Earthshine polarization spectra obtained with FORS2 on the VLT, covering diverse scenes, surface conditions, cloud properties, and weather patterns for over a decade. For the first time, we model this extensive dataset in detail using a homogeneous modeling framework. Previous efforts to model some of these spectra struggled to reproduce the observed polarization continuum, even with advanced 3D radiative transfer models incorporating satellite-derived surface and atmospheric data. We improve upon this with a 3D model that includes subgrid cloud variability, wavelength-dependent surface albedo maps, and an accurate treatment of ocean glint. Our simulations successfully reproduce most observed spectra to a much higher precision than previously possible. Our statistical analysis reveals that the spectral slope in the visible can distinguish between ocean and mixed surfaces in both reflected and polarized light, which is not possible using broadband filters alone. Polarized light at large phase angles, beyond the Rayleigh scattering regime, is particularly effective in differentiating oceans from land, unlike reflected light. We also identify correlations between cloud optical thickness and the polarized spectral slope, and between cloud cover and broadband B-R differences in reflected light, demonstrating the diagnostic power of these observations. This work highlight the potential of polarization for characterizing Earth-like exoplanets. From polarization alone, we can infer oceans, vegetation, and an active water cycle, key indicators of a habitable planet.

The RadMap Telescope is a compact instrument designed to characterize the primary spectrum of cosmic-ray nuclei and the secondary radiation field created by their interaction with the shielding of spacecraft. Its main purpose is to precisely monitor the radiation exposure of astronauts, and it is the first instrument with a compact form factor that can measure both the charge and energy of individual nuclei with energies up to several GeV per nucleon. This capability is enabled by a tracking calorimeter made from scintillating-plastic fibers, which can record the energy-loss profile of particles in three dimensions and with nearly omnidirectional sensitivity. We present first results from the RadMap Telescope's first orbital deployment on the International Space Station between April 2023 and January 2024.

Luminosities of pre-main sequence stars evolve during the protoplanetary disc lifetime. This has a significant impact on the heating of their surrounding protoplanetary disks, the natal environments of planets. Moreover, stars of different masses evolve differently. However, this is rarely accounted for in planet formation models. We carry out pebble-driven core accretion planet formation modelling with focus on the impact of pre-main sequence stellar luminosity evolution on giant planet formation around host stars in the range of <inline-formula><tex-math id="TM0001" notation="LaTeX">$1{-}2.4\ \rm M_{\odot }$</tex-math></inline-formula>. We find that giant planet formation is sensitive to the evolution of stellar luminosity, specifically the locations and times at which giant planet formation can occur depend on it. High stellar luminosity causes an increase in the scale height of the gas and pebbles, which may decrease the efficiency of pebble accretion, making it more challenging to form giant planets. This has important consequences for the composition of these giant planets, stressing the need to incorporate such aspects into planet formation models.

Early stages of stellar birth comprise of a two-step process involving the formation of two hydrostatic cores. The second step of gravitational collapse sets the radiative efficiency and accretion rate of the young protostar. These two parameters, of prime importance for protostellar evolution, dictate the luminosities and thus play a key role in deciphering the current discrepancy between observational surveys and theoretical models. In this letter, we provide quantitative estimates on the evolution of the radiative efficiency and accretion rate obtained from self-consistent, high-resolution, radiative hydrodynamic simulations performed using the codes PLUTO and RAMSES. The main highlight of our result is that the radiative efficiency reaches unity, that is, supercriticality, relatively quickly after protostellar birth. Supercriticality at the accretion shock is a necessary condition for cold accretion. Our results thus support a rapid transition to the cold accretion scenario, which is one of the assumptions used in Pre-Main Sequence (PMS) models working towards solutions to explain observational data. We briefly discuss the implications of the time evolution of the radiative efficiency factor in the context of the luminosity problem, the Protostellar Luminosity Function (PLF), PMS evolution, accurate sink properties, and the stellar Initial Mass Function (IMF).

Detailed knowledge of the radiation environment in space is an indispensable prerequisite for space missions in low Earth orbit and beyond. The RadMap Telescope is a compact radiation monitor that can characterize the radiation environment aboard spacecraft and determine the biologically relevant dose received by astronauts. Its main sensor is a tracking calorimeter made from 1024 scintillating-plastic fibers of alternating orientation and silicon photomultipliers. It allows the three-dimensional tracking and identification of cosmic-ray nuclei by measurement of their energy-deposition profiles.

The properties of nuclei traversing the detector are reconstructed using a neural-network-based analysis framework. In this contribution, we describe the three consecutive convolutional networks that we use to determine the track parameters, charge, and initial kinetic energy of each nucleus as well as the challenges of a network-based analysis approach. We demonstrate the capabilities of our framework with networks trained and evaluated on simulated data and show that the achieved performance is in agreement with the requirements of radiation monitoring. Finally, we discuss the significance of our results and the limitations of both the analysis framework and the detector.

Based on the scale-free nature of gravity, the structure in the Universe is expected to be self-similar on large scales. However, this self-similarity eventually breaks down due to small-scale gas physics such as star formation, active galactic nucleus (AGN) and stellar feedback, and non-linear effects gaining importance relative to linear structure formation. In this work, we investigate the large-scale matter flows that connect collapsed structures to their cosmic environments. Specifically, we focus on their agreement with self-similarity in various properties. For this purpose we used the full power of the hydrodynamical cosmological simulation suite Magneticum Pathfinder to precisely calculate the instantaneous inflow and outflow rates of structures on a large range of masses and redshifts. We find a striking self-similarity across the whole mass range and through time that only breaks down in the outflowing regime due to the different outflow driving mechanisms for galaxies versus galaxy clusters. We additionally performed a geometrical analysis of the patterns of inflow versus outflow to demonstrate how the inflows organise into anisotropic filaments driven by the tidal distortions of the environment, while the outflows are fairly isotropic due to their thermal nature. This also manifests in the differences in the thermal and chemical properties of the gas in the inflowing and outflowing component: While the inflowing gas is pristine and colder, encountering the accretion shock surfaces and entering the influence region of AGN and stellar feedback heats the gas up into a diffuse metal-enriched hot atmosphere. Overall the differences between outflowing and infalling gas are enhanced at the galaxy cluster scale compared to the galaxy scale due to the strong accretion shocks that reach out to large radii for these objects. An individual study of the gas motions in the outskirts of one of the most massive clusters in the simulations we carried out demonstrates these results to greater detail: Gas found in the outer (r > 1.2r_vir) hot atmosphere at z = 0 falls in and is completely enriched early in the assembly process before being shock heated and expanding.

The de novo synthesis of life from non-living matter represents a bold scientific challenge, advancing our understanding of life's minimal requirements and offering revolutionary applications in biotechnology. We explore fuel-dependent synthetic cells based on complex coacervate droplets, which lack membranes and readily take up reactants. Given their fuel-dependent nature, these droplets emerge and grow when fuel is abundant but dissolve under starvation conditions, mimicking the non-equilibrium nature of life. However, their ability to produce offspring—a key requirement for life—has remained elusive. Moreover, their rescue in repetitive fueling-starvation experiments has not been demonstrated. Our work elucidates a mechanism of producing offspring by synthetic cells driven by solid-like speckles in droplets liberated as offspring. By fine-tuning parameters, we control offspring number and survival. Finally, refueling sustains second-generation synthetic cells. This system provides a platform for coupling offspring production with self-replicating molecules, paving the way for synthetic cells capable of Darwinian evolution.

The dispersion measure (DM) of fast radio bursts (FRBs) is sensitive to the electron distribution in the Universe, making it a promising probe of cosmology and astrophysical processes such as baryonic feedback. However, cosmological analyses of FRBs require knowledge of the contribution to the observed DM coming from the FRB host. The size and distribution of this contribution is still uncertain, thus significantly limiting current cosmological FRB analyses. In this study, we extend the baryonification (BCM) approach to derive a physically-motivated, analytic model for predicting the host contribution to FRB DMs. By focusing on the statistical properties of FRB host DMs, we find that our simple model is able to reproduce the probability distribution function (PDF) of host halo DMs measured from the CAMELS suite of hydrodynamic simulations, as well as their mass- and redshift dependence. Furthermore, we demonstrate that our model allows for self-consistent predictions of the host DM PDF and the matter power spectrum suppression due to baryonic effects, as observed in these simulations, making it promising for modelling host-DM-related systematics in FRB analyses. In general, we find that the shape of the host DM PDF is determined by the interplay between the FRB and gas distributions in halos. Our findings indicate that more compact FRB profiles require shallower gas profiles (and vice versa) in order to match the observed DM distributions in hydrodynamic simulations. Furthermore, the analytic model presented here shows that the shape of the host DM PDF is highly sensitive to the parameters of the BCM. This suggests that this observable could be used as an interesting test bed for baryonic processes, complementing other probes due to its sensitivity to feedback on galactic scales. We further discuss the main limitations of our analysis, and point out potential avenues for future work.

The age of the Local Bubble (LB) can be used to constrain the timescales, on which the interstellar medium in the solar neighborhood is evolving. Previous estimates have put the age of the LB at $\gtrsim 14\,\text{Myr}$, and suggested that its expansion was powered by $\sim 15-20$ SNe, yet in a companion paper we have seen hints that this age might be too high. Following up on these hints, we aim to place new constraints on the age of the LB. We reconstruct the geometry and momentum of the LB using publicly available 3D dust maps to compare its geometry to that of the high-quality sample of simulated supernova remnants in the SISSI project. We find that, in contrast to previous estimates, $\gtrsim 20$ SNe over $\sim 4\,\text{Myr}$ are required to explain both the momentum and the size of the LB. The julia source-code for our analysis is made available at doi.org/10.5281/zenodo.17054923. Previous estimates of the age of the LB have seemingly overestimated its age and underestimated the number of SNe powering its expansion. Our results are in tension with the assumption that the LB is powered solely by SNe associated with the nearby Scorpius-Centraurus OB association, which appears to have stopped forming stars at about the same time as the LB began to expand. In light of this new evidence, our results cast serious doubts on the claim that star formation in the solar neighborhood was driven by the expansion of the LB, and might have instead quenched it.

We present a view of the stellar halo in the inner-central regions of the Milky Way (R ≲ 10 kpc) mapped by RR Lyrae stars. The combined BRAVA-RR/APOGEE RR Lyrae catalog is used to obtain a sample of 281 RR Lyrae stars located in the bulge region of the Galaxy, but with orbits indicating they belong to the inner-central halo. The RR Lyrae stars in the halo are more metal-poor than the bulge RR Lyrae stars and have pulsation properties more consistent with an accreted population. We use the Milky Way-like zoom-in cosmological simulation Auriga to compare the properties of the RR Lyrae stars to those expected from the "Gaia-Enceladus-Sausage" (GES) merger. The integrals of motions and eccentricities of the RR Lyrae stars are consistent with a small fraction of 6–9% ± 2% of the inner-central halo RR Lyrae population having originated from GES. This fraction, lower than what is seen in the solar neighborhood, is consistent with trends seen in the Auriga simulation, where a GES-like merger would have a decreasing fraction of GES stars at small Galactocentric radii compared to other accreted populations. Very few of the Auriga inner Galaxy GES-18 particles have properties consistent with belonging to a bulge population with (z_max < 1.1 kpc), indicating that no (or very few) RR Lyrae stars with bulge orbits should have originated from GES.

Supermassive black hole feedback is the currently favoured mechanism to regulate the star formation rate of galaxies and prevent the formation of ultra-massive galaxies (M_⋆ > 10¹² M_⊙). However, the mechanism through which the outflowing energy is transferred to the surrounding medium strongly varies from one galaxy evolution model to another, such that a unified model for active galactic nucleus (AGN) feedback does not currently exist. The hot atmospheres of galaxy groups are highly sensitive laboratories of the feedback process, as the injected black hole energy is comparable to the binding energy of halo gas particles. Here we report multi-wavelength observations of the fossil galaxy group SDSSTG 4436. The hot atmosphere of this system exhibits a highly relaxed morphology centred on the giant elliptical galaxy NGC 3298. The X-ray emission from the system features a compact core (< 10 kpc) and a steep increase in the entropy and cooling time of the gas, with the cooling time reaching the age of the Universe ∼15 kpc from the centre of the galaxy. The observed entropy profile implies a total injected energy of ∼1.5 × 10⁶¹ ergs, which given the high level of relaxation could not have been injected by a recent merging event. Star formation in the central galaxy NGC 3298 is strongly quenched and its stellar population is very old (∼10.6 Gyr). The currently detected radio jets have low power and are confined within the central compact core. All the available evidence implies that this system was affected by giant AGN outbursts that raised the entropy of the neighbouring gas to the point that the gas no longer efficiently cools. Our findings imply that AGN outbursts can be energetic enough to unbind gas particles and lead to the disruption of cool cores.

We study magnetic conversion of ultra-relativistic axion-like particles (ALPs) into photons in compact-star environments, focusing on the hot, transient conditions of core-collapse supernova (SN) remnants and neutron-star mergers (NSMs). We address previously overlooked uncertainties, particularly the suppression caused by ejected matter near the stellar surface, a region crucial to the conversion process. We derive analytical expressions for the transition rate; they reveal the influence of key parameters and their uncertainties. We update constraints using historical gamma-ray data from SN~1987A and find $g_{aγ}<5\times10^{-12}~{\rm GeV}^{-1}$ for $m_a\lesssim10^{-9}$ meV. We also forecast sensitivities for a future Galactic SN and for NSMs, assuming observations with Fermi-LAT or similar gamma-ray instruments. We distinguish ALPs -- defined as coupling only to photons and produced via Primakoff scattering -- from axions, which also couple to nucleons and emerge through nuclear bremsstrahlung. We omit pionic axion production due to its large uncertainties and inconsistencies, though it could contribute comparably to bremsstrahlung under optimistic assumptions. For the compact sources, we adopt time-averaged one-zone models, guided by numerical simulations, to enable clear and reproducible parametric studies.

Gravitational-wave (GW) neutron star mergers with an associated electromagnetic counterpart constitute powerful probes of binary evolution, the production sites of heavy elements, general relativity, and the expansion of the Universe. Only a handful of candidate GW binary mergers during the fourth LIGO/Virgo/KAGRA observing run (O4) so far are believed to include a neutron star. We present optical–near-infrared follow-up observations of the candidate neutron star–black hole GW merger S250206dm. This is the first high-significance mass-gap neutron star–black hole candidate observed by multiple GW detectors (thus having a significantly smaller sky localization than one-detector events), offering the first opportunity to effectively follow up a GW event of this kind. Our GW MultiMessenger Astronomy DECam Survey (GW-MMADS) campaign consisted of a wide-field search using the Dark Energy Camera (DECam) and T80-South (T80S), as well as galaxy-targeted observations using the Southern Astrophysical Research (SOAR) imager and the Fraunhofer Telescope at Wendelstein Observatory. No viable kilonova counterpart was found in our observations. We use our observation depths to place competitive constraints on kilonova models similar to or brighter than the GW170817 kilonova AT 2017gfo within our observed fields, ruling out 100% of such models with SOAR galaxy-targeted observations and ∼43% (48%) with DECam (DECam and T80S).

Galaxy clusters are the largest collapsed structures in the universe. Using the halo mass function (HMF), we can predict the number of clusters within a mass range for a fixed redshift. The HMF, however, depends on cosmological parameters such as the total matter density, Ωₘ, and the amplitude of matter density fluctuations, σ₈. Consequently, the observed number of galaxy clusters can provide constraints on these parameters. Since cluster masses are not directly observable, scaling relations that link observable properties to true cluster masses are crucial. In this context, understanding the creation of galaxy cluster catalogs—including selection and confirmation processes—and accurately constraining the parameters of the observable-mass relation are fundamental for the use of cluster number counts as cosmological probes.

My first study focuses on the analysis of the merging galaxy cluster SPT-CL J0307-6225. Through an analysis of its merging dynamics, I separate the substructures and find a likely mass ratio of ~1.3. On the other hand, the analysis of the galaxy population hints towards a previous merger in one of the substructures.

In my second study, I use galaxy cluster candidates, selected using the thermal Sunyaev-Zeldovich effect with data from the Planck (down to S/N= 3), and look for optical counterparts using photometric data from the Dark Energy Survey data release 3. The final catalog, PSZ-MCMF, contains over 800 confirmed clusters with a purity of 90\%.

In the third study I demonstrate how to use a X-ray selected and optically confirmed galaxy cluster sample (RASS-MCMF) to get cosmology constrains. Using a mock cluster sample with properties similar to the 99\% pure subset of RASS-MCMF (~5000 clusters), I forecast constraining powers of 0.026, 0.033, and 0.15 (1σ) for the parameters Ωₘ, σ₈, and w respectively.

Finally, in my fourth study, I expand the analysis from the third study by improving the modeling of the RASS-MCMF sample. These improvements include a new method for the abundance likelihood and the explicit inclusion of weak-lensing mass calibration. The results indicate that these improvements yield constraining power comparable to the latest results from SPT and eRASS1.

We present a global neutrino oscillation analysis of models with a single large extra dimension in which right-handed neutrinos possess bulk Dirac masses. Two scenarios are considered: large extra dimensions with bulk masses and the dark dimension framework, both predicting a tower of sterile Kaluza-Klein states that mix with active neutrinos. Using data from MINOS/MINOS+, KamLAND, and Daya Bay, we perform a joint likelihood analysis. No signatures of these theories were found. Therefore, we constrain the compactification radius under different bulk mass and Yukawa coupling assumptions. Large positive bulk masses or sizable Yukawas lead to strong bounds, while small couplings or negative bulk masses remain less constrained.

Context. The cosmic time evolution of the radial structure is one of the key topics in the investigation of disc galaxies. In the build-up of galactic discs, gas infall is an important ingredient and it produces radial gas inflows as a physical consequence of angular momentum conservation since the infalling gas onto the disc at a specific radius has lower angular momentum than the circular motions of the gas at the point of impact. NGC 300 is a well-studied isolated, bulgeless, and low-mass disc galaxy ideally suited for an investigation of galaxy evolution with radial gas inflows. Aims. Our aim is to investigate the effects of radial gas inflows on the physical properties of NGC 300, for example the radial profiles of HI gas mass and star formation rate (SFR) surface densities, specific star formation rate (sSFR), and metallicity, and to study how the metallicity gradient evolves with cosmic time. Methods. A chemical evolution model for NGC 300 was constructed by assuming its disc builds up progressively by the infalling of metal-poor gas and the outflowing of metal-enriched gas. Radial gas inflows were also considered in the model. We used the model to build a bridge between the available data (e.g. gas content, SFR, and chemical abundances) observed today and the galactic key physical processes. Results. Our model including the radial gas inflows and an inside-out disc formation scenario can simultaneously reproduce the present-day observed radial profiles of HI gas mass surface density, SFR surface density, sSFR, gas-phase, and stellar metallicity. We find that, although the value of radial gas inflow velocity is as low as ‑0.1 km s^‑1, the radial gas inflows steepen the present-day radial profiles of HI gas mass surface density, SFR surface density, and metallicity, but flatten the radial sSFR profile. Incorporating radial gas inflows significantly improves the agreement between our model predicted present-day sSFR profile and the observations of NGC 300. Our model predictions are also in good agreement with the star-forming galaxy main sequence and the mass-metallicity relation of star-forming galaxies. It predicts a significant flattening of the metallicity gradient with cosmic time. We also find that the model predicted star formation has been more active recently, indicating that the radial gas inflows may help to sustain star formation in local spirals, at least in NGC 300.

Fast neutrino flavor conversion may impact the explosion mechanism and nucleosynthesis in core-collapse supernovae. A necessary condition for fast flavor conversion is the presence of crossings in the angular distribution of the electron-neutrino lepton number (ELN) crossing. Because of the computational costs, flavor-dependent angular distributions are not computed by the vast majority of state-of-the-art hydrodynamical simulations; instead, angular distributions are reconstructed employing approximate methods in postprocessing. In this work, we evaluate the performance of four methods adopted to diagnose the existence of ELN crossings. For selected postbounce times, we extract the fluid and thermodynamic properties from spherically symmetric supernova simulations for an <inline-formula><mml:math><mml:mrow><mml:mn>18.6</mml:mn><mml:msub><mml:mrow><mml:mi>M</mml:mi></mml:mrow><mml:mrow><mml:mo>⊙</mml:mo></mml:mrow></mml:msub></mml:mrow></mml:math></inline-formula> progenitor, testing cases with and without muons as well as with and without mixing-length treatment of protoneutron star convection. We compare the occurrence of crossings in the angular distributions obtained by solving the Boltzmann equations with those in distributions reconstructed from angular moments of our Boltzmann solutions by using the maximum entropy and Minerbo schemes, and also with crossings identified via a polynomial weighting function applied to the angular moments. Our results show that the polynomial method and the Minerbo closure scheme have severe limitations. The maximum entropy approach captures most of the forward crossings, although it fails to reproduce or misidentifies crossings in a subset of our models. These findings highlight the need for robust modeling of the neutrino angular properties in order to assess the impact of flavor conversion on the supernova mechanism.