We present the first gamma-ray burst (GRB) host galaxy with a measured absorption line and electron temperature (T<inline-formula><tex-math>$_e$</tex-math></inline-formula>) based metallicity, using the temperature sensitive [O III]<inline-formula><tex-math>$\lambda$</tex-math></inline-formula>4363 auroral line detected in the JWST/NIRSpec spectrum of the host of GRB 050505 at redshift <inline-formula><tex-math>$z=4.28$</tex-math></inline-formula>. We find that the metallicity of the cold interstellar gas, derived from the absorption lines in the GRB afterglow, of 12 + log(O/H) <inline-formula><tex-math>$\sim 7.7$</tex-math></inline-formula> is in reasonable agreement with the temperature-based emission line metallicity in the warm gas of the GRB host galaxy, which has values of 12 + log(O/H) = 7.80<inline-formula><tex-math>$\pm$</tex-math></inline-formula>0.19 and 7.96<inline-formula><tex-math>$\pm$</tex-math></inline-formula>0.21 for two common indicators. When using strong emission line diagnostics appropriate for high-z galaxies and sensitive to ionization parameter, we find good agreement between the strong emission line metallicity and the other two methods. Our results imply that, for the host of GRB050505, mixing between the warm and the cold interstellar medium along the line of sight to the GRB is efficient, and that GRB afterglow absorption lines can be a reliable tracer of the metallicity of the galaxy. If confirmed with a large sample, this suggest that metallicities determined via GRB afterglow spectroscopy can be used to trace cosmic chemical evolution to the earliest cosmic epochs and in galaxies far too faint for emission line spectroscopy, even for JWST.

The large $N$ analysis of QCD states that the potential for the $η'$ meson develops cusps at $η' = π/ N_f$, $3 π/N_f$, $\cdots$, with $N_f$ the number of flavors. Furthermore, the recent discussion of generalized anomalies tells us that even for finite $N$ there should be cusps if $N$ and $N_f$ are not coprime, as one can show that the domain wall configuration of $η'$ should support a Chern-Simons theory on it, i.e., domains are not smoothly connected. On the other hand, there is a supporting argument for instanton-like, smooth potentials of $η'$ from the analyses of softly-broken supersymmetric QCD for $N_f= N-1$, $N$, and $N+1$. We argue that the analysis of the $N_f = N$ case should be subject to the above anomaly argument, and thus there should be a cusp; while the $N_f = N \pm 1$ cases are consistent, as $N_f$ and $N$ are coprime. We discuss how this cuspy/smooth transition can be understood. For $N_f< N$, we find that the number of branches of the $η'$ potential is $\operatorname{gcd}(N,N_f)$, which is the minimum number allowed by the anomaly. We also discuss the condition for s-confinement in QCD-like theories, and find that in general the anomaly matching of the $θ$ periodicity indicates that s-confinement can only be possible when $N_f$ and $N$ are coprime. The s-confinement in supersymmetric QCD at $N_f = N+1$ is a famous example, and the argument generalizes for any number of fermions in the adjoint representation.

Shocks are promising sites of particle acceleration in extragalactic jets. In electron-ion shocks, electrons can be heated up to large Lorentz factors, making them an attractive scenario to explain the high minimum electron Lorentz factors regularly needed to describe the emission of BL Lac objects. Still, the thermal electron component is commonly neglected when modelling the observations, although it holds key informations on the shock properties. We model the broadband emission of the HSP blazar Mrk421 employing particle distributions that include a thermal relativistic Maxwellian component at low energies followed by a nonthermal power-law, as motivated by PIC simulations. The observations in the optical/UV and MeV-GeV bands efficiently restrict the nonthermal emission from the Maxwellian electrons, which we use to derive constraints on the basic properties, such as the fraction $ε_e$ of the total shock energy stored in the nonthermal electrons. The best-fit model yields a nonthermal electron power-law with an index of ~2.4, close to predictions from shock acceleration. Successful fits are obtained when the ratio between the Lorentz factor at which the nonthermal distribution begins ($γ_{\rm nth}$) and the dimensionless electron temperature ($θ$) satisfies $γ_{\rm nth}/θ\lesssim 8$. Since $γ_{\rm nth}/θ$ controls $ε_e$, the latter limit implies that at least $ε_e \approx 10\%$ of the shock energy is transferred to the nonthermal electrons. These results are almost insensitive to the shock velocity $γ_{\rm sh}$, but radio observations indicate $γ_{\rm sh} \gtrsim 5$ since for lower shock velocities the radio fluxes are overproduced by the Maxwellian electrons. If shocks drive the particle energisation, our findings indicate that they operate in the mildly to fully relativistic regime with efficient electron acceleration.

Blazars are promising high-energy neutrino source candidates. Yet, leptohadronic models face challenges in describing neutrino emission within a viable energy budget, and their predictive power is limited by the commonly used single-zone approximation and the reliance on phenomenological parameters. In this work, we present a new leptohadronic model where a sub-Eddington jet evolves from magnetically- to kinetically dominated. A small fraction of the electrons and protons picked up by the jet are continuously accelerated to a power-law spectrum, estimated based on the local magnetic field strength, turbulence, and ambient density, for which we assume power-law profiles. The model parameters are thus directly tied to the jet physics and are comparable in number to typical single-zone models. We then numerically calculate the emission along the jet. Applying the model to the IceCube candidate TXS 0506+056, we find that protons are accelerated to EeV energies in the inner jet, producing a neutrino flux up to order 100 PeV that is consistent with the public 10 year IceCube point-source data. Proton emission at 0.1 pc describes the X-ray and gamma-ray data, while electron emission at the parsec scale describes the optical data. Protons carry a power of about 1% of the Eddington luminosity, showing that the model is energetically viable. The particle spectra follow $E^{-1.8}$, with diffusion scaling as $E^{0.3}$, ruling out Bohm-like diffusion. Additional particle injection near the broad line region can reproduce the 2017 flare associated to a high-energy neutrino. We also apply the model to blazar PKS 0605-085, which may be associated with a recent neutrino detected by KM3NeT above 100 PeV. The results suggest that blazars are efficient neutrino emitters at ultra-high energies, making them prime candidates for future experiments targeting this challenging energy range.

We present a neural-network framework designed to reconstruct the properties of cosmic-ray nuclei traversing the scintillating-fiber tracking calorimeter of the RadMap Telescope. Employing the Geant4 simulation toolkit and a simplified model of the detector to generate training and test data, we achieve the spectroscopic capabilities required for an accurate determination of the biologically relevant dose that astronauts receive in space. We can reconstruct a particle's trajectory with an angular resolution of better than $1.4^\circ$ and achieve a charge separation of better than $95\%$ for nuclei with $Z\leq8$; specifically, we reach an accuracy of $99.8\%$ for hydrogen. The energy resolution is $<20\%$ for energies below 1 GeV/n and elements up to iron. We also discuss the limitations of our detector, the reconstruction framework, and this feasibility study, as well as possible improvements.

We present simulations of the supernova-driven turbulent interstellar medium (ISM) in a simulation domain of volume (256 pc)³ within which we resolve the formation of protostellar accretion disks and their stellar cores to spatial scales of ~10^-4 au, using the moving-mesh code AREPO. We perform simulations with no magnetic fields, ideal magnetohydrodynamics (MHD) and ambipolar diffusion, and compare the resulting first Larson cores and their associated structures, including the accretion disks, their location within the larger-scale structure and the streamers connecting these. We find that disks of sizes 10 - 100 au form early in the simulations without magnetic fields, while there are no disks larger than 10 au with ideal MHD. Ambipolar diffusion causes large disks to form in a subset of cases (two out of six cores), and generally reduces the strength of outflows, which are seen to play a central role. When they are able to carry away significant angular momentum, they prevent the formation of a rotationally supported disk. Magnetic fields strengths grow from 0.1 - 1 mG in the protostellar core to more than 10 G in the first Larson core in all simulations with ideal MHD. The rotationally supported disks which form can have rotation speeds >1 km s^-1 even out to further than 100 au from the centre, become gravitationally unstable and form complex spiral substructures with Toomre Q < 1. We conclude that the impact of magnetic fields and non-ideal MHD on the formation of protostellar disks is substantial in realistic formation scenarios from the turbulent ISM.

The innermost parts of the Milky Way (MW) are very difficult to observe due to the high extinction along the line of sight, especially close to the disc mid-plane. However, this region contains the most massive complex stellar component of the MW, the bulge, primarily composed of disc stars whose structure is (re-)shaped by the evolution of the bar. In this work, we extend the application of the orbit superposition method to explore the present-day 3D structure, orbital composition, chemical abundance trends and kinematics of the MW bulge. Thanks to our approach, we are able to transfer astrometry from Gaia and stellar parameters from APOGEE DR 17 to map the inner MW without obscuration by the survey footprint and selection function. We demonstrate that the MW bulge is made of two main populations originating from a metal-poor, high-α thick disc and a metal-rich, low-α thin disc, with a mass ratio of 4:3, seen as two major components in the metallicity distribution function (MDF). Finer MDF structures hint at multiple sub-populations associated with different orbital families of the bulge, which, however, have broad MDFs themselves. Decomposition using 2D Gaussian Mixture Models in the [Fe/H]-[Mg/Fe] plane identifies five components, including a population with ex-situ origin. Two dominant ones correspond to the thin and thick discs, and two in between trace the transition between them. We show that there is no universal metallicity gradient value that can characterise the MW bulge. The radial gradients closely trace the X-shaped bulge density structure, while the vertical gradient variations follow the boxy component. The MW bulge, while on average having subsolar metallicity, is more metal-rich compared to the surrounding disc populations, in agreement with extragalactic observations and state-of-the-art simulations, reinforcing its secular origin.

We describe an attempt of string theoretic derivation of the Gibbons-Hawking entropy. Despite not admitting a de Sitter vacuum, the string theory, by the power of open-close correspondence, captures the Gibbons-Hawking entropy as the entropy of Chan-Paton species on a de Sitter-like state obtained via D-branes. Moreover, this derivation sheds a new light at the origin of the area-form, since the equality takes place for a critical 't Hooft coupling for which the species entropy of open strings saturates the area-law unitarity bound.

In this exploratory work we analyze the possible existence of a strangeness <inline-formula><mml:math><mml:mrow><mml:mi>S</mml:mi><mml:mo>=</mml:mo><mml:mo>-</mml:mo><mml:mn>3</mml:mn></mml:mrow></mml:math></inline-formula>, isospin <inline-formula><mml:math><mml:mrow><mml:mi>I</mml:mi><mml:mo>=</mml:mo><mml:mn>1</mml:mn></mml:mrow></mml:math></inline-formula> pentaquark state <inline-formula><mml:math><mml:msub><mml:mi>P</mml:mi><mml:mrow><mml:mi>sss</mml:mi></mml:mrow></mml:msub></mml:math></inline-formula> generated dynamically from the <inline-formula><mml:math><mml:mrow><mml:mover><mml:mrow><mml:mi>K</mml:mi></mml:mrow><mml:mrow><mml:mo>¯</mml:mo></mml:mrow></mml:mover><mml:mi>Ξ</mml:mi></mml:mrow></mml:math></inline-formula> interaction. We employ a unitarized scheme in coupled channels based on the chiral Lagrangian expanded up to next-to-leading order (NLO), and show that the inclusion of the NLO terms can be crucial to provide the necessary attraction that favors the existence of such triply strange pentaquark. The <inline-formula><mml:math><mml:mrow><mml:mover><mml:mrow><mml:mi>K</mml:mi></mml:mrow><mml:mrow><mml:mo>¯</mml:mo></mml:mrow></mml:mover><mml:mi>Ξ</mml:mi></mml:mrow></mml:math></inline-formula> femtoscopic correlation functions are calculated as example of a possible experimental measurement in which a direct signal of the <inline-formula><mml:math><mml:msub><mml:mi>P</mml:mi><mml:mrow><mml:mi>sss</mml:mi></mml:mrow></mml:msub></mml:math></inline-formula> state could be observed.

Red supergiants (RSGs), which are progenitors of hydrogen-rich Type II supernovae (SNe), have been known to pulsate from both observations and theory. The pulsations can be present at core collapse and affect the resulting SN. However, SN light curve models of such RSGs commonly use hydrostatic progenitor models and ignore pulsations. Here, we model the final stages of a 15 solar-mass RSG and self-consistently follow the hydrodynamical evolution. We find the growth of large amplitude radial pulsations in the envelope. After a transient phase where the envelope restructures, the pulsations settle to a steady and periodic oscillation with a period of 817 days. We show that they are driven by the $κγ$-mechanism, which is an interplay between changing opacities and the release of recombination energy of hydrogen and helium. This leads to complex and non-coherent expansion and contraction in different parts of the envelope, which greatly affect the SN progenitor properties, including its location in the Hertzsprung-Russell diagram. We simulate SN explosions of this model at different pulsations phases. Explosions in the compressed state result in a flat light curve (Type II-P). In contrast, the SN light curve in the expanded state declines rapidly, reminiscent of a Type II-L SN. For cases in between, we find light curves with various decline rates. Features in the SN light curves are directly connected to features in the density profiles. These are in turn linked to the envelope ionization structure, which is the driving mechanism of the pulsations. We predict that some of the observed diversity in Type II SN light curves can be explained by RSG pulsations. For more massive RSGs, we expect stronger pulsations that might even lead to dynamical mass ejections of the envelope and to an increased diversity in SN light curves.

Context. The distribution of chemical elements in star-forming regions can store information on the chemical enrichment history of galaxies and particularly of recent events. Negative metallicity gradients are expected in galaxies forming inside-out. Azimuthal-averaged profiles are usually fit to the projected chemical distributions to quantify them. However, observations show that the metallicity profiles can be broken. Aims. We aim to study the diversity of metallicity profiles that can arise in the current cosmological context and compare them with available observations. Additionally, we seek to identify the physical processes responsible for breaks in metallicity profiles by using two galaxies as case studies. Methods. We analyzed central galaxies from the cosmological simulations of CIELO project, with stellar masses within the range of 10^8.5 to 10^10.5 M_⊙ at z = 0. A new algorithm, DB-A, was developed to fit multiple power laws to the metallicity profiles, enabling a flexible assessment of metallicity gradients in various galactic regions. The simulations include detailed modeling of gas components, metal-dependent cooling, star formation, and supernova feedback. Results. At z = 0, we find a diversity of shapes, with inner and outer drops and rises, and there are a few galaxies with double breaks. Inner, outer, and middle gradients are in agreement with observations. We also find that using a single linear regression to fit gradients usually traces the middle gradient well. A detailed temporal analysis of the main galaxies of a Local Group analog revealed the occurrence of inner and outer breaks at all cosmic times, with the latter being the most common feature during the evolution of our case studies. Significant variability in the metallicity gradients was found at high redshift, transitioning to more gradual evolution at lower redshifts. Most of the inner breaks have enhanced oxygen abundances in the center, which are linked to gas accretion followed by efficient star formation. Inner breaks with diluted oxygen abundances are less common and are found in galaxies with disrupted gas distributions which are affected by feedback-driven ejection of enriched gas. Outer breaks with high abundances are linked to processes such as the re-accretion of enriched material, extended star formation, and enhanced gas mixing from the circumgalactic medium. Outer breaks with diluted metallicities in the outskirts are found mainly at high redshift and are associated with the accretion of metal-poor gas from cold flows. We also highlight and illustrate the complex interplay of these processes which act often together.

Recent hydrodynamical simulations of isolated barred disc galaxies have suggested a structural change in the distribution of the interstellar medium (ISM) around a stellar mass M_* of 10¹⁰ M_⊙. In the higher-mass regime (M_∗ ≥ 10¹⁰ M_⊙), we observe the formation of a central gas and stellar disc with a typical size of a few hundred parsecs connected through lanes to the ends of the stellar bar. In the lower-mass regime (M_∗ < 10¹⁰ M_⊙), such an inner disc is absent and the gas component exhibits a more chaotic distribution. Observations of nearby star-forming galaxies support the existence of such a change. These inner gas discs may represent an important intermediate scale connecting the large kiloparsec-scale structures with the nuclear (sub-parsec) region, transporting gas inwards to fuel the central supermassive black hole (SMBH). For this work we used an extended set of high-resolution hydrodynamical simulations of isolated disc galaxies with initial properties (i.e. stellar mass, gas fraction, stellar disc scale length, and the bulge mass fraction) with properties covering the range of galaxies in the PHANGS sample to investigate this change of regime. We studied the physical properties of the star-forming ISM in both stellar mass regimes and extracted a few physical tracers: the inner Lindblad resonance (ILR), the probability distribution function (PDF), the virial parameter, and the Mach number. In line with observations, we confirm a structure transition in the simulations that occurs between a stellar mass of 10^9.5 and 10¹⁰ M_⊙. We show that the physical origin of this change of regime is driven by stellar feedback and its contribution relative to the underlying gravitational potential. With their shallower potential and typically higher gas mass fraction, lower-mass disc PHANGS galaxies combine two ingredients that significantly delay or even prevent the formation of a central gas (and stellar) disc. These results shed some light on the observed properties of star-forming barred galaxies and have implications for the star formation regimes, the growth of central structures, and the overall secular evolution of disc galaxies.

We investigate the high-ionization, narrow [Ne V] λ3427 line emission in a sample of over 340 ultrahard X-ray (14–195 keV) selected active galactic nuclei (AGN) drawn from the BAT AGN Spectroscopic Survey project. The analysis includes measurements in individual and stacked spectra and considers several key AGN properties such as X-ray luminosity, supermassive black hole (SMBH) mass, Eddington ratios, and line-of-sight column density. The [Ne V] λ3427 line is robustly detected in ≈43% (146/341) of the AGN in our sample, with no significant trends between the detection rate and key AGN/SMBH properties. In particular, the detection rate remains high even at the highest levels of obscuration (>70% for <inline-formula> <mml:math><mml:mi>log</mml:mi><mml:mfenced><mml:mrow><mml:msub><mml:mi>N</mml:mi><mml:mi>H</mml:mi></mml:msub><mml:mo>/</mml:mo><mml:msup><mml:mi>cm</mml:mi><mml:mrow><mml:mo>‑</mml:mo><mml:mn>2</mml:mn></mml:mrow></mml:msup></mml:mrow></mml:mfenced><mml:mo>)</mml:mo><mml:mo>≳</mml:mo><mml:mn>23</mml:mn></mml:math> </inline-formula>). On the other hand, even some of our highest signal-to-noise spectra (S/N > 50) lack a robust [Ne v] detection. The typical (median) scaling ratios between [Ne v] line emission and (ultra)hard X-ray emission in our sample are <inline-formula> <mml:math><mml:mi>log</mml:mi><mml:msub><mml:mrow><mml:mi>L</mml:mi></mml:mrow><mml:mrow><mml:mo>[</mml:mo><mml:mi>Ne</mml:mi><mml:mspace></mml:mspace><mml:mi>V</mml:mi><mml:mo>]</mml:mo></mml:mrow></mml:msub><mml:mo>/</mml:mo><mml:msub><mml:mrow><mml:mi>L</mml:mi></mml:mrow><mml:mrow><mml:mn>14</mml:mn><mml:mo>‑</mml:mo><mml:mn>150</mml:mn><mml:mspace></mml:mspace><mml:mi>keV</mml:mi></mml:mrow></mml:msub><mml:mo>≃</mml:mo><mml:mo>‑</mml:mo><mml:mn>3.75</mml:mn></mml:math> </inline-formula> and <inline-formula> <mml:math><mml:mi>log</mml:mi><mml:msub><mml:mrow><mml:mi>L</mml:mi></mml:mrow><mml:mrow><mml:mo>[</mml:mo><mml:mi>Ne</mml:mi><mml:mspace></mml:mspace><mml:mi>V</mml:mi><mml:mo>]</mml:mo></mml:mrow></mml:msub><mml:mo>/</mml:mo><mml:msub><mml:mrow><mml:mi>L</mml:mi></mml:mrow><mml:mrow><mml:mn>2</mml:mn><mml:mo>‑</mml:mo><mml:mn>10</mml:mn><mml:mspace></mml:mspace><mml:mi>keV</mml:mi></mml:mrow></mml:msub><mml:mo>≃</mml:mo><mml:mo>‑</mml:mo><mml:mn>3.36</mml:mn></mml:math> </inline-formula>. The scatter on these scaling ratios, ≲0.5 dex, is comparable to, and indeed smaller than, what is found for other commonly used tracers of AGN radiative outputs (e.g., [O III] λ5007). Otherwise, we find no significant relations between the (relative) strength of [Ne v] and the basic AGN/SMBH properties under study, in contrast with simple expectations from models of SMBH accretion flows. Our results reaffirm the usability of [Ne v] as an AGN tracer even in highly obscured systems, including dual AGN and high-redshift sources.

Aims. We investigated the gas reservoirs, star formation properties, and environment of the ultra-diffuse galaxy GAMA 526784 to understand its formation history, the efficiency of molecular gas conversion into stars, and the possible role of an interacting companion in shaping its current morphology. Methods. We analysed low- and high-resolution CO observations to place constraints on the molecular gas content of the galaxy, compared them with HI data, and examined the star formation efficiency of GAMA 526784. The potential influence of a newly identified nearby dwarf galaxy was assessed using photometric and spatial information. Results. GAMA 526784 exhibits a regular HI reservoir (M_HI/M_⋆ = 2.88), but we are only able to place upper limits on its molecular gas mass (M_H2(5σ)/M_⋆ < 0.23). The galaxy's HI reservoir and CO non-detection can be explained by several mechanisms: (1) the predominance of CO-dark H₂, which remains invisible to CO observations but contributes to star formation; (2) a time delay in HI-to-H₂ conversion following a recent interaction; or (3) elevated turbulence inhibiting gas collapse. An identified companion, optically found at a projected distance of ∼48 kpc, shows similar colours and lies in the direction of the young star clusters in GAMA 526784, indicating a possible association. We hypothesise that this companion may have triggered the formation of the star clusters in GAMA 526784 through a high-velocity encounter. Conclusions. Our findings suggest that GAMA 526784 may have undergone a dwarf–dwarf interaction that significantly influenced its gas reservoirs and star formation activity. The presence of a nearby companion galaxy is consistent with predictions of a high-speed encounter, potentially offering a rare observational example of such an interaction in progress. We hypothesise that this encounter may have played a key role in shaping the system's recent evolution. Future observations, particularly targeting molecular gas tracers beyond CO and resolved HI observations, will be crucial in determining the true extent of GAMA 526784's cold gas reservoir and the nature of its recent star formation activity.

Aims. Pulsating variable stars are invaluable tracers for reconstructing the star formation history and chemical evolution of their host galaxies. In this work, we explore the variable star population of Leo II, a distant dwarf spheroidal satellite of the Milky Way. Methods. We analyse an extensive dataset of ground-based BVRI time-series photometry spanning over 35 years. By examining the properties of RR Lyrae stars, we constrain the early chemical enrichment and spatial variation within Leo II. Additionally, we investigate the anomalous Cepheids in order to connect their characteristics with the galaxy's prolonged star formation history, as revealed by deep HST/WFC3 colour–magnitude diagrams. Results. We identified and characterised 175 variable stars, with all but one associated with Leo II. Our work includes the discovery of 25 new RR Lyrae stars and two new anomalous Cepheids. Moreover, we reclassified V88 as a BL Her variable star. By employing multiple independent methods, including metallicity-luminosity relations for RR Lyrae stars and period–luminosity and period–Wesenheit relations for both RR Lyrae and anomalous Cepheids, we derived a true distance modulus of (m ‑ M)₀ = 21.60 ± 0.03 mag, corresponding to 209 ± 4 kpc. Furthermore, we discuss potential formation scenarios for anomalous Cepheids and suggest that, despite the extended star formation history, they are all compatible having originated from old binary stars, with no contribution from young, evolved single stars.

The stellar disc is the dominant luminous component of the Milky Way (MW). Although our understanding of its structure is rapidly expanding due to advances in large-scale surveys of stellar populations across the Galaxy, our picture of the disc remains substantially obscured by selection functions and an incomplete spatial coverage of observational data. In this work, we present the comprehensive chrono-chemo-kinematic structure of the MW disc, recovered using a novel orbit superposition approach combined with data from APOGEE DR 17. We detected periodic azimuthal metallicity variations within 6–8 kpc with an amplitude of 0.05–0.1 dex peaking along the bar major axis. The radial metallicity profile of the MW also varies with azimuth, displaying a pattern typical among other disc galaxies, namely: a decline outside the solar radius and an almost flat profile in the inner region, attributed to the presence of old, metal-poor high-α populations, comprising ≈40% of the total stellar mass. The geometrically defined thick disc and the high-α populations have comparable masses, but with differences in their stellar population content, which we quantified using the reconstructed 3D MW structure. The well-known [α/Fe]-bimodality in the MW disc, once it has been weighted by the stellar mass, is less pronounced at a given metallicity for the whole galaxy but distinctly visible in a narrow range of galactic radii (5–9 kpc), explaining its relative lack of prominence in external galaxies and galaxy formation simulations. Analysing a more evident double age–abundance sequence, we constructed a scenario for the MW disc formation, advocating for an inner and outer disc dichotomy genetically linked to the MW's evolutionary stages. In this picture, the extended solar vicinity is a transition zone that shares the chemical properties of both the inner (old age-metallicity sequence) and outer discs (young age-metallicity sequence).

AT 2019aalc is a peculiar sequence of highly variable emission events observed towards the nucleus of the broad-line active galactic nucleus (AGN) SDSS J152416.66+045119.0. The system exhibited two distinct UV-optical flares (the first detected in 2019, the second one in 2023). Spectra obtained following the detection of the second flare revealed prominent Bowen fluorescence (BF) and high-ionization coronal emission lines, which were much weaker, if at all detectable, in a spectrum taken following the first flare. We present and analyze a large set of multi-wavelength, multi-epoch data for this source, with particular emphasis on optical spectroscopic monitoring conducted with the Las Cumbres Observatory network. During the relatively slow dimming that followed the second optical flare, the UV-optical light curve shows a sequence of minor rebrightening events, while the BF and the coronal lines vary (roughly) in tandem with these "bumps" in the broadband light curve. Most of the observed behavior of AT 2019aalc links it to the growing class of BF flares while setting it apart from canonical tidal disruption events. However, AT 2019aalc has some outstanding peculiarities, including two short flares seen in its soft X-ray light-curve during the dimming phase of the second optical flare, and which do not seem to be linked to the emission line variations. We discuss the optical and X-ray properties of the source and possible scenarios of the origin of the flare, in particular radiation pressure instabilities in the (preexisting) AGN accretion disk.

Context. Dark matter (DM) particles can interact with particles characterised by the standard model. Although there are a number of constraints derived from direct and indirect detection experiments, the dynamical evolution of astrophysical objects could offer a promising probe for such interactions. Obtaining astrophysical predictions is challenging and primarily limited by our ability to simulate scattering between DM and baryonic particles within N-body and hydrodynamics simulations. Aims. We have developed the first scheme allowing for the simulation of these interacting dark matter (IDM) models, accurately accounting for their angular and velocity dependence, as well as the mass ratio between the DM and baryonic scattering partners. Methods. To describe DM-baryon interactions, we used an N-body code together with its implementation of smoothed-particle hydrodynamics (SPH) and meshless finite mass. The interaction itself was realised in a pairwise fashion by creating a virtual scattering partner from the baryonic particle and allowing it to interact with a DM particle using a scattering routine initially developed for self-interacting dark matter (SIDM). After the interaction, the virtual particle is rejoined with the baryonic particle, fulfilling the requirements of energy and momentum conservation. Results. Through several test problems, we demonstrated that we are able to reproduce the analytic solutions with our IDM scheme. This includes a test for scattering with a physical mass ratio of 1:1000, which is beyond the limits of current SIDM simulations. We comment on various numerical aspects and challenges, and we describe the limitations of our numerical scheme. Furthermore, we study the impact of IDM on halo formation with a collapsing over-density. Conclusions. We find that it is possible to accurately model IDM within N-body and hydrodynamics simulations commonly used in astrophysics. Finally, our scheme allows for novel predictions to be made and new constraints on DM-baryon scattering to be set.

Neutrinos experience collective flavor conversion in extreme astrophysical environments such as core-collapse supernovae (CCSNe). One manifestation of collective conversion is slow flavor conversion (SFC), which has recently attracted renewed interest owing to its ubiquity across different regions of the supernova environment. In this study, we systematically examine the evolution of kinematic decoherence in a dense neutrino gas undergoing SFC, considering lepton number asymmetries as large as 30%. Our findings show that the neutrino gas asymptotically evolves toward a generic state of coarse-grained flavor equilibration which is constrained by approximate lepton number conservation. The equilibration occurs within a few factors of the inverse vacuum oscillation frequency, <inline-formula><mml:math><mml:msup><mml:mi>ω</mml:mi><mml:mrow><mml:mo>-</mml:mo><mml:mn>1</mml:mn></mml:mrow></mml:msup></mml:math></inline-formula>, which corresponds to (anti)neutrinos reaching near flavor equipartition after a few kilometers for typical supernova neutrino energies. Notably, the quasisteady state of the neutrino number densities can be quantitatively described by the neutrino-antineutrino number density ratio <inline-formula><mml:math><mml:msub><mml:mi>n</mml:mi><mml:msub><mml:mover><mml:mi>ν</mml:mi><mml:mo>¯</mml:mo></mml:mover><mml:mi>e</mml:mi></mml:msub></mml:msub><mml:mo>/</mml:mo><mml:msub><mml:mi>n</mml:mi><mml:msub><mml:mi>ν</mml:mi><mml:mi>e</mml:mi></mml:msub></mml:msub></mml:math></inline-formula> alone. Such a simple estimation opens new opportunities for incorporating SFC into CCSN simulations, particularly in regions where SFC develops on scales much shorter than those of collisions.

Galaxy groups and clusters are among the best probes of structure formation and growth in a cosmological context. Most of their baryonic component is dominated by hot plasma, known as the intracluster medium (ICM) in clusters or the intragroup medium (IGrM) in groups. Their thermodynamical properties serve as indicators of the halo's dynamical state and can be used to determine halo mass in the self-similar scenario. However, baryonic processes, such as AGN feedback and gas cooling, may affect the global properties of the ICM, especially in the group regime. These effects might lead to deviations from self-similar predictions in the scaling relations of galaxy groups, while they remain in place for massive galaxy clusters. Additionally, the low-mass end of the scaling relations, ranging from 10¹³ to 10¹⁴ M_⊙, remains unclear and poorly populated, as current X-ray surveys detect only the brightest groups. Here, we present the mass-temperature relation across the entire mass range, from massive clusters to low-mass groups (10¹³ M_⊙), as observed by eROSITA. Using spectral stacking from the first eROSITA All-Sky Survey data for optically selected galaxy groups, we find that, in the lower mass range, galaxy groups follow the power-law relation known for galaxy clusters. We provide the best-fit mass–temperature relation, validated over two decades in halo mass, as follows: log₁₀(M₅₀₀/M_⊙) = (1.65 ± 0.11)ṡlog₁₀(T_X/1 keV)+(13.38 ± 0.05). We further validate these results by conducting the same stacking procedure on mock eRASS:4 data using the MAGNETICUM hydrodynamical simulation. This indicates that AGN feedback is more likely to affect the distribution of baryons in the intragroup medium rather than the overall halo gas temperature. No significant changes in the slope of the mass-temperature relation suggest that temperature can serve as a reliable mass proxy across the entire mass range. This supports the use of temperature-derived masses, particularly in cosmological studies, significantly broadening the mass range and enabling applications such as improving cluster mass function studies and cosmological parameter estimates.

The characterization of nearby rocky exoplanets will become feasible with the next generation of telescopes, such as the Extremely Large Telescope (ELT) and the mission concept Habitable Worlds Observatory (HWO). Using an improved model setup, we aim to refine the estimates of reflected and polarized light contrast for a selected sample of rocky exoplanets in the habitable zones of nearby stars. We perform advanced 3D radiative transfer simulations for Earth-like planets orbiting G-type and M-type stars. Our simulations incorporate realistic, wavelength-dependent surface albedo maps and a detailed cloud treatment, including 3D cloud structures and inhomogeneities, to better capture their radiative response. These improvements are based on Earth observations. We present models of increasing complexity, ranging from simple homogeneous representations to a detailed Earth-as-an-exoplanet model. Our results show that averaging homogeneous models fails to capture Earth's full complexity, especially in polarization. Moreover, simplistic cloud models distort the representation of absorption lines at high spectral resolutions, particularly in water bands, potentially biasing atmospheric chemical abundance estimates. Additionally, we provide updated contrast estimates for observing rocky exoplanets around nearby stars with upcoming instruments such as ANDES and PCS at the ELT. Compared to previous studies, our results indicate that reflected light contrast estimates are overestimated by a factor of two when simplified cloud and surface models are used. Instead, measuring the fractional polarization in the continuum and in high-contrast, high-resolution spectra may be more effective for characterizing nearby Earth-like exoplanets. These refined estimates are essential for guiding the design of future ELT instruments and the HWO mission concept.

We study the generalized charm susceptibilities in <inline-formula><mml:math><mml:mrow><mml:mn>2</mml:mn><mml:mo>+</mml:mo><mml:mn>1</mml:mn></mml:mrow></mml:math></inline-formula> flavor QCD on the lattice at several lattice spacings. We show that, below the chiral crossover, these susceptibilities are well described by the hadron resonance gas (HRG) model if charmed hadrons not listed in tables of the Particle Data Group are included. However, the HRG description abruptly breaks down just above the chiral crossover. To understand this, we use a model for the charm pressure in which it is expressed as the sum of partial pressures from charmed baryons, charmed mesons, and charm quarks. We present continuum estimates of these partial pressures and find that, while the partial pressures of charmed mesons and baryons drop below their respective HRG predictions, the charm quark pressure becomes nonzero above the chiral crossover.

We investigate the spectral behavior of scalar fluctuations generated by gravity during inflation and the subsequent reheating phase. We consider a nonperturbative Bogoliubov treatment within the context of pure gravitational reheating. We compute both long- and short-wavelength spectra, first for a massless scalar field, revealing that the spectral index in part of the infrared (IR) regime varies between <inline-formula><mml:math><mml:mo>-</mml:mo><mml:mn>6</mml:mn></mml:math></inline-formula> and <inline-formula><mml:math><mml:mo>-</mml:mo><mml:mn>3</mml:mn></mml:math></inline-formula>, depending on the postinflationary equation of state (EoS), <inline-formula><mml:math><mml:mn>0</mml:mn><mml:mo>≤</mml:mo><mml:msub><mml:mi>w</mml:mi><mml:mi>ϕ</mml:mi></mml:msub><mml:mo>≤</mml:mo><mml:mn>1</mml:mn></mml:math></inline-formula>. Furthermore, we study the mass-breaking effect of the IR spectrum by including the finite mass, <inline-formula><mml:math><mml:msub><mml:mi>m</mml:mi><mml:mi>χ</mml:mi></mml:msub></mml:math></inline-formula>, of the daughter scalar field. We show that for <inline-formula><mml:math><mml:msub><mml:mi>m</mml:mi><mml:mi>χ</mml:mi></mml:msub><mml:mo>/</mml:mo><mml:msub><mml:mi>H</mml:mi><mml:mi>e</mml:mi></mml:msub><mml:mo>≳</mml:mo><mml:mn>3</mml:mn><mml:mo>/</mml:mo><mml:mn>2</mml:mn></mml:math></inline-formula>, where <inline-formula><mml:math><mml:msub><mml:mi>H</mml:mi><mml:mi>e</mml:mi></mml:msub></mml:math></inline-formula> is the Hubble parameter during inflation, the IR spectrum of scalar fluctuations experiences exponential mass suppression, while for smaller masses, <inline-formula><mml:math><mml:msub><mml:mi>m</mml:mi><mml:mi>χ</mml:mi></mml:msub><mml:mo>/</mml:mo><mml:msub><mml:mi>H</mml:mi><mml:mi>e</mml:mi></mml:msub><mml:mo><</mml:mo><mml:mn>3</mml:mn><mml:mo>/</mml:mo><mml:mn>2</mml:mn></mml:math></inline-formula>, the spectrum remains flat in the IR regime regardless of the postinflationary EoS. For any general EoS, we also compute a specific IR scale, <inline-formula><mml:math><mml:msub><mml:mi>k</mml:mi><mml:mi>m</mml:mi></mml:msub></mml:math></inline-formula>, of fluctuations below which the IR spectrum will suffer from this finite mass effect. In the UV regime, oscillations of the inflaton background lead to interference terms that explain the high-frequency oscillations in the spectrum. Interestingly, we find that for any EoS, <inline-formula><mml:math><mml:mn>1</mml:mn><mml:mo>/</mml:mo><mml:mn>9</mml:mn><mml:mo>≲</mml:mo><mml:msub><mml:mi>w</mml:mi><mml:mi>ϕ</mml:mi></mml:msub><mml:mo>≲</mml:mo><mml:mn>1</mml:mn></mml:math></inline-formula>, the spectral behavior turns out to be independent of the EoS, with a spectral index <inline-formula><mml:math><mml:mo>-</mml:mo><mml:mn>6</mml:mn></mml:math></inline-formula>. We have compared this Bogoliubov treatment for the UV regime to perturbative computations with solutions to the Boltzmann equation and found an agreement between the two approaches for any EoS, <inline-formula><mml:math><mml:mn>0</mml:mn><mml:mo>≲</mml:mo><mml:msub><mml:mi>w</mml:mi><mml:mi>ϕ</mml:mi></mml:msub><mml:mo>≲</mml:mo><mml:mn>1</mml:mn></mml:math></inline-formula>. We also explore the relationship between the gravitational reheating temperature and the reheating EoS employing the nonperturbative analytic approach, finding that reheating can occur for <inline-formula><mml:math><mml:msub><mml:mi>w</mml:mi><mml:mi>ϕ</mml:mi></mml:msub><mml:mo>≳</mml:mo><mml:mn>0.6</mml:mn></mml:math></inline-formula>.

The decay of metastable false-vacuum states via bubble nucleation plays a crucial role in many cosmological scenarios. Cold-atom analog experiments will soon provide the first empirical probes of this process, with potentially far-reaching implications for early-universe cosmology and high-energy physics. However, an inevitable difference between these analog systems and the early universe is that the former have a boundary. We show, using a combination of Euclidean calculations and real-time lattice simulations, that these boundaries generically cause rapid bubble nucleation on the edge of the experiment, obscuring the bulk nucleation that is relevant for cosmology. We demonstrate that implementing a high-density trench region at the boundary completely eliminates this problem and recovers the desired cosmological behavior. Our findings are relevant for ongoing efforts to probe vacuum decay in the laboratory, providing a practical solution to a key experimental obstacle.

Line intensity mapping (LIM) is an emerging technique for probing the large scale structure (LSS) in the post-reionisation era. This captures the integrated flux of a particular spectral line emission from multiple sources within a patch of the sky without resolving them. Mapping different galaxy line emissions, such as the HI $21$-cm and CO rotational lines via LIM, can reveal complementary information about the bias with which the line emitters trace the underlying matter distribution and how different astrophysical phenomena affect the clustering pattern of these signals. The stage where the structures in the cosmic web merge to form a single connected structure is known as the percolation transition. Using mock HI $21$-cm and CO($1-0$) LIM signals in the post-reionisation universe, we explore the connectivity of structures through percolation analysis and compare it with that of the underlying galaxy distribution. We probe the relative contributions of voids, filaments, and sheets to the galaxy density and line intensity maps using a morphological measure known as the local dimension. The CO($1-0$) map exhibits an increased filamentary behaviour and larger contribution from sheets than the $21$-cm map. We attempt to explain such an emission of the CO($1-0$) line from biased environments. The upcoming SKA-Mid will produce tomographic intensity maps of the $21$-cm signal at $z \lesssim 3$ in Band-1. CO maps can be produced at these redshifts in phase 2 of SKA-Mid, where the frequency coverage is expected to increase up to $\sim 50$ GHz. We present forecasts for the recovery of the local dimensions of these intensity maps contaminated by instrumental noise, considering SKA-Mid observations.

Atmospheres of transiting exoplanets can be studied spectroscopically using space-based or ground-based observations. Each has its own strengths and weaknesses, so there are benefits to both approaches. This is especially true for challenging targets such as cooler, smaller exoplanets whose atmospheres likely contain many molecular species and cloud decks. We aim to study the atmosphere of the warm Neptune-like exoplanet WASP-107 b (Teq~740 K). Several molecular species have been detected in this exoplanet in recent space-based JWST studies, and we aim to confirm and expand upon these detections using ground-based VLT, evaluating how well our findings agree with previously retrieved atmospheric parameters. We observe two transits of WASP-107 b with VLT/CRIRES+ and create cross-correlation templates of the target atmosphere based on retrieval results from JWST studies. We create different templates to investigate the impact of varying volume mixing ratios of species and inclusion or exclusion of clouds. Considering this target's observational challenges, we create simulated observations prior to evaluating real data to assess expected detection significances. We report detections of two molecular species, CO (~6 S/N) and H2O (~4.5 S/N). This confirms previous space-based detections and demonstrates, for the first time, the capability of VLT/CRIRES+ to detect species in targets cooler than hot Jupiters using transmission spectroscopy. We show our analysis is sensitive to cloud inclusion, but less so to different volume mixing ratios. Interestingly, our detection deviates from its expected location in our Kp-vsys diagrams, and we speculate on possible reasons for this. We demonstrate that the error budget for relatively cooler exoplanets is severely reduced in comparison to hotter exoplanets, and underline need for further work in context of high-resolution spectroscopy.

Precise predictions for Higgs decays are a crucial ingredient of the search for beyond the Standard Model (BSM) physics and the Standard Model Effective Field Theory (SMEFT) is a valuable tool for quantifying deviations from the Standard Model (SM). We present the complete set of predictions for the 2- and 3- body Higgs decays at next-to-leading order (NLO), considering QCD and electroweak corrections and including all contributions from the dimension-6 SMEFT operators and with an arbitrary flavor structure. Including the NLO SMEFT results for Higgs decays greatly increases the sensitivity to BSM physics of the $e^+e^-\rightarrow Zh$ process at FCC-ee, as compared with that obtained using only the total cross section.

The C-MetaLL project has provided homogeneous spectroscopic abundances of 290 Classical Cepheids (DCEPs) for which we have the intensity-averaged magnitudes in multiple optical and near-infrared (NIR) bands, periods, pulsation modes, and Gaia parallaxes. Our goal is to derive updated period--Wesenheit--metallicity (PWZ) relations using the largest and most homogeneous metallicity sample ever used for such analyses, covering a range of $-1.3<$[Fe/H]$<+0.3$ dex. We computed several optical and NIR Wesenheit magnitudes using 275 DCEPs with reliable parallaxes, by applying a robust photometric parallax technique, which simultaneously fits all parameters -- including the global Gaia parallax counter-correction -- and handles outliers without data rejection. We find a stronger metallicity dependence ($γ\approx -0.5$ mag/dex in optical, $-0.4$ mag/dex in NIR) than recent literature reports. Gaia parallax zero-point conter-corrections ($ε$) vary smoothly across bands, with an average value of $\sim$10 $μ$as, aligning with previous determinations. Applying our PWZ relations to LMC Cepheids yields distances generally consistent within $1σ$ with geometric estimates. The choice of reddening law has a negligible impact, while using only fundamental-mode pulsators significantly increases the uncertainties. Including $α$-element corrections increases $|γ|$ and reduces $ε$. However, we find statistically consistent $γ$ values with the literature, particularly for the key Wesenheit magnitude in the HST bands, by restricting the sample to the brighter (i.e. closer) objects, or by including only pulsators with $-0.7<$[Fe/H]$<$0.2 dex. Our results hint at a large $γ$ or a non-linear dependence on metallicity of DCEP luminosities at the metal-poor end, which is difficult to quantify with the precision of parallaxes of the present dataset.

We generalize the framework of spurion analysis to a class of selection rules arising from non-invertible fusion algebras in perturbation theory. As a first step toward systematic applications to particle physics, we analyze the near-group fusion algebras, defined by fusion rules built from a finite Abelian group $G$ extended by a single non-invertible element. Notable examples include the Fibonacci and Ising fusion rules. We introduce a systematic scheme for labeling coupling constants at the level of the non-invertible fusion algebra, enabling consistent tracking of couplings when constructing composite amplitudes from simpler building blocks. Our labeling provides a clear interpretation of why the tree-level exact non-invertible selection rules are violated through radiative corrections, a unique phenomenon essential to ``loop-induced groupification''. We also identify the limit where the near-group fusion algebra is lifted to a $G\times \mathbb{Z}_2$ group, which provides an alternative scheme of spurion analysis consistent with the original one based on the near-group algebra. Meanwhile, we highlight the distinctions between the selection rules imposed by the near-group fusion algebra and those from breaking the $G\times \mathbb{Z}_2$ group.

We present ProMage, a feed-forward neural network that emulates the computation of observer- and rest-frame magnitudes from the generative galaxy SED package ProSpect. The network predicts magnitudes conditioned on input galaxy physical properties, including redshift, star formation history, gas and dust parameters. ProMage accelerates magnitude computation by a factor of $10^4$ compared to ProSpect, while achieving per-mille relative accuracy for $99\%$ of sources in the test set across the $g,r,i,z,y$ Hyper Suprime-Cam bands. This acceleration is key to enabling fast inference of galaxy physical properties in next-generation Stage IV surveys and to generating large catalogue realisations in forward-modelling frameworks such as GalSBI-SPS.

Various so-called anomalies have been found in both the WMAP and Planck cosmic microwave background (CMB) temperature data that exert a mild tension against the highly successful best-fit 6 parameter cosmological model, potentially providing hints of new physics to be explored. That these are real features on the sky is uncontested. However, given their modest significance, whether they are indicative of true departures from the standard cosmology or simply statistical excursions, due to a mildly unusual configuration of temperature anisotropies on the sky which we refer to as the "fluke hypothesis", cannot be addressed further without new information. No theoretical model of primordial perturbations has to date been constructed that can explain all of the temperature anomalies. Therefore, we focus in this paper on testing the fluke hypothesis, based on the partial correlation between the temperature and $E$-mode CMB polarisation signal. In particular, we compare the properties of specific statistics in polarisation, built from unconstrained realisations of the $Λ$CDM cosmological model as might be observed by the LiteBIRD satellite, with those determined from constrained simulations, where the part of the $E$-mode anisotropy correlated with temperature is constrained by observations of the latter. Specifically, we use inpainted Planck 2018 SMICA temperature data to constrain the $E$-mode realisations. Subsequent analysis makes use of masks defined to minimise the impact of the inpainting procedure on the $E$-mode map statistics. We find that statistical assessments of the $E$-mode data alone do not provide any evidence for or against the fluke hypothesis. However, tests based on cross-statistical measures determined from temperature and $E$ modes can allow this hypothesis to be rejected with a moderate level of probability.

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 slight changes in this threshold also explored) in the Milky Way subject to be followed up by future massive spectroscopic surveys, we have developed a Gaia DR3 plus literature data based methodology. We trained a Balanced Random Forest (BRF) with the spectral types from the compilation by Skiff et al. (2014) as labels. Our approach yields a completeness of $\sim80\%$ and a purity ranging from $0.51 \pm 0.02$ for probabilities between 0.6 and 0.7, up to $0.85 \pm 0.05$ 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 in 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 $\sim$50\%. As a byproduct, we developed an automatic methodology for spectral typing optimized for LAMOST spectra, based on line detection and characterization guiding a decision path.

The thermal confinement phase transition (PT) in $SU(N)$ Yang-Mills theory is first-order for $N\geq 3$, with bounce action scaling as $N^2$. Remarkably, lattice data for the action include a small coefficient whose presence likely strongly alters the PT dynamics. We give evidence, utilizing insights from softly-broken SUSY YM models, that the small coefficient originates from a deconfined phase instability just below the critical temperature. We predict the maximum achievable supercooling in $SU(N)$ theories to be a few percent, which can be tested on the lattice. We briefly discuss the potentially significant suppression of the associated cosmological gravitational wave signals.

Many galactic globular clusters (GCs) contain at least two stellar populations. Recent observational studies found that the radial distributions of the first (P1) and second population (P2) differ in dynamically-young GCs. Since P2 is conventionally assumed to form more centrally concentrated, the rapid mixing (or even inversion) in some GCs but not others is puzzling. We investigate whether dynamical processes specific to certain GCs might cause this. Specifically, we evaluate the expansion of P2 by binary-single interactions in the cluster core and whether these can mix the P1/P2 radial distributions, using a set of toy-models with varying numbers and masses of primordial binaries. We find that even one massive binary star can push the central P2 outwards, but multiple binaries are required to fully mix P1 and P2 within a few relaxation times. We also compare our results to observed properties of mixed young GCs (NGC 4590, 5053, or 5904).

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 (MS) or red giant (RG) 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 $\sim5-45$ ($\sim1-8$) detectable UCXBs in the Milky Way (Andromeda galaxy), including $\sim1$ 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 $\sim 10^3$ 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 study the approach to equilibrium of bottomonium in the quark-gluon plasma within the open quantum system framework. We perform large-scale simulations of the long-time behavior in three dimensions using the quantum trajectory method to observe the emergence of steady states and determine the timescale of thermalization in position-, angular-momentum-, and color-space. We find that the thermalization timescale increases with decreasing temperature and decreasing coupling to the medium, which is given by transport coefficients of the medium. Additionally, we observe that the steady states exhibit small corrections to the Gibbs state due to medium interactions and show that these corrections diminish for weaker medium coupling and higher temperature. At a temperature of $450\,$MeV, quarkonium relaxes to a state that is approximately thermal, with the most significant correction being a smaller overlap of the $1S$ state with respect to the Gibbs state. We compare these findings with the master equation obtained at leading order in the expansion of the binding energy over the temperature, which we find to have a trivial steady state.

Two detector modules with lithium aluminate targets were operated in the CRESST underground setup between February and June 2021. The data collected in this period was used to set the currently strongest cross-section upper limits on the spin-dependent interaction of dark matter (DM) with protons and neutrons for the mass region between 0.25 and 1.5 GeV/c$^2$. The data are available online. In this document, we describe how the data set should be used to reproduce our dark matter results.

A flux of ultra-high-energy (UHE) neutrinos is generally expected to be produced by astrophysical sources at cosmological distances and to reach Earth. In this paper, we investigate the impact of neutrino scattering with dark matter (DM) particles in both the intergalactic medium and the Milky Way on the total flux, energy spectrum, and arrival directions of UHE neutrinos. We emphasize the complementarity of neutrino detectors at different latitudes to probe the anisotropy in the flux at Earth due to the attenuation of the neutrino flux in the Milky Way dark matter halo. We also discuss that, with mild astrophysical assumptions, limits on the DM-$ν$ scattering cross section can be placed even if the neutrino sources are unknown. Finally, we explore all this phenomenology with the recent UHE neutrino event KM3230213A, and place the corresponding limits in the DM-$ν$ scattering cross-section.

The majority of Galactic globular star clusters (GCs) have been reported to contain at least two populations of stars (we use P1 for the primordial and P2 for the chemically-enriched population). Recent observational studies found that dynamically-old GCs have P1 and P2 spatially mixed due to relaxation processes. However, in dynamically-young GCs, where P2 is expected to be more centrally concentrated from birth, the spatial distributions of P1 and P2 are sometimes very different from system to system. This suggests that more complex dynamical processes specific to certain GCs might have shaped those distributions. We aim to investigate the discrepancies between the spatial concentration of P1 and P2 stars in dynamically-young GCs. Our focus is to evaluate whether massive binary stars (e.g. BHs) can cause the expansion of the P2 stars through binary-single interactions in the core, and whether they can mix or even radially invert the P1 and P2 distributions. We use a set of theoretical and empirical arguments to evaluate the effectiveness of binary-single star scattering. We then construct a set of direct N-body models with massive primordial binaries to verify our estimates further and gain more insights into the dynamical processes in GCs. We find that binary-single star scatterings can push the central P2 stars outwards within a few relaxation times. While we do not produce radial inversion of P1 and P2 for any initial conditions we tested, this mechanism systematically produces clusters where P1 and P2 look fully mixed even in projection. The mixing is enhanced 1) in denser GCs, 2) in GCs containing more binary stars, and 3) when the mass ratio between the binary components and the cluster members is higher. Binary-single star interactions seem able to explain the observable properties of some dynamically-young GCs (e.g. NGC4590 or NGC5904) where P1 and P2 are fully radially mixed.

The motivic coaction of multiple zeta values and multiple polylogarithms encodes both structural insights on and computational methods for scattering amplitudes in a variety of quantum field theories and in string theory. In this work, we propose coaction formulae for iterated integrals over holomorphic Eisenstein series that arise from configuration-space integrals at genus one. Our proposal is motivated by formal similarities between the motivic coaction and the single-valued map of multiple polylogarithms at genus zero that are exposed in their recent reformulations via zeta generators. The genus-one coaction of this work is then proposed by analogies with the construction of single-valued iterated Eisenstein integrals via zeta generators at genus one. We show that our proposal exhibits the expected properties of a coaction and deduce $f$-alphabet decompositions of the multiple modular values obtained from regularized limits.

Self-assembly processes in biological and synthetic biomolecular systems are often governed by the spatial separation of biochemical processes. While previous work has focused on optimizing self-assembly through fine-tuned reaction parameters or using phase-separated liquid compartments with fast particle exchange, the role of slow inter-compartmental exchange remains poorly understood. Here, we demonstrate that slow particle exchange between reaction domains can enhance self-assembly efficiency through a cooperative mechanism: delay-facilitated assembly. Using a minimal model of irreversible self-assembly in two compartments with distinct reaction and exchange dynamics, we identify scenarios that maximize yield and minimize assembly time, even under conditions where isolated compartments would fail to facilitate any self-assembly. The mechanism relies on a separation of timescales between intra-compartmental reactions and inter-compartmental exchange and is robust across a wide range of geometries, including spatially extended domains with diffusive transport. We demonstrate that this effect enables geometric control of self-assembly processes through compartment volumes and exchange rates, eliminating the need for fine-tuning local reaction rates. These results offer a conceptual framework for leveraging spatial separation in synthetic self-assembly design and suggest that biological systems may use slow particle exchange to improve assembly efficiency.

Quantum higher-spin theory applied to Compton amplitudes has proven to be surprisingly useful for elucidating Kerr black hole dynamics. Here we apply the framework to compute scattering amplitudes and observables for a binary system of two rotating black holes, at second post-Minkowskian order, and to all orders in the spin-multipole expansion for certain quantities. Starting from the established three-point and conjectured Compton quantum amplitudes, the infinite-spin limit gives classical amplitudes that serve as building blocks that we feed into the unitarity method to construct the 2-to-2 one-loop amplitude. We give scalar box, vector box, and scalar triangle coefficients to all orders in spin, where the latter are expressed in terms of Bessel-like functions. Using the Kosower-Maybee-O'Connell formalism, the classical 2PM impulse is computed, and in parallel we work out the scattering angle and eikonal phase. We give novel all-order-in-spin formulae for certain contributions, and the remaining ones are given up to <inline-formula><mml:math><mml:mi>O</mml:mi><mml:mfenced><mml:msup><mml:mi>S</mml:mi><mml:mn>11</mml:mn></mml:msup></mml:mfenced></mml:math></inline-formula>. Since Kerr 2PM dynamics beyond <inline-formula><mml:math><mml:mi>O</mml:mi><mml:mfenced><mml:msup><mml:mi>S</mml:mi><mml:mrow><mml:mo>≥</mml:mo><mml:mn>5</mml:mn></mml:mrow></mml:msup></mml:mfenced></mml:math></inline-formula> is as of yet not completely settled, this work serves as a useful reference for future studies.

We study the generation of gravitational waves (GWs) during a cosmological first-order phase transition (PT) using the recently introduced Higgsless approach to numerically simulate the fluid motion induced by the PT. We present for the first time GW spectra sourced by bulk fluid motion in the aftermath of strong first-order PTs (α = 0.5), alongside weak (α = 0.0046) and intermediate (α = 0.05) PTs, previously considered in the literature. We find that, for intermediate and strong PTs, the kinetic energy in our simulations decays, following a power law in time. The decay is potentially determined by non-linear dynamics and hence related to the production of vorticity. We show that the assumption that the source is stationary in time, characteristic of compressional motion in the linear regime (sound waves), agrees with our numerical results for weak PTs, since in this case the kinetic energy does not decay with time. We then provide a theoretical framework that extends the stationary assumption to one that accounts for the time evolution of the source: as a result, the GW energy density is no longer linearly increasing with the source duration, but proportional to the integral over time of the squared kinetic energy fraction. This effectively reduces the linear growth rate of the GW energy density and allows to account for the period of transition from the linear to the non-linear regimes of the fluid perturbations. We validate the novel theoretical model with the results of simulations and provide templates for the GW spectrum for a broad range of PT parameters.

We evaluate the three-loop five-point pentagon-box-box massless integral family in the dimensional regularization scheme, via canonical differential equation. We use tools from computational algebraic geometry to enable the necessary integral reductions. The boundary values of the differential equation are determined analytically in the Euclidean region. To express the final result, we introduce a new representation of weight six functions in terms of one-fold integrals over the product of weight-three functions with weight-two kernels that are derived from the differential equation. Our work paves the way to the analytic computation of three-loop multileg Feynman integrals.

Cosmic birefringence (CB) is the rotation of the photons' linear polarisation plane during propagation. Such an effect is a tracer of parity-violating extensions of standard electromagnetism and would probe the existence of a new cosmological field acting as dark matter or dark energy. It has become customary to employ cosmic microwave background (CMB) polarised data to probe such a phenomenon. Recent analyses on Planck and WMAP data provide a hint of detection of the isotropic CB angle with an amplitude of around 0.3° at the level of 2.4 to 3.6σ. In this work, we explore the LiteBIRD capabilities in constraining such an effect, accounting for the impact of the more relevant systematic effects, namely foreground emission and instrumental polarisation angles. We build five semi-independent pipelines and test these against four different simulation sets with increasing complexity in terms of non-idealities. All the pipelines are shown to be robust and capable of returning the expected values of the CB angle within statistical fluctuations for all the cases considered. We find that the uncertainties in the CB estimates increase with more complex simulations. However, the trend is less pronounced for pipelines that account for the instrumental polarisation angles. For the most complex case analysed, we find that LiteBIRD will be able to detect a CB angle of 0.3° with a statistical significance ranging from 5 to 13σ, depending on the pipeline employed, where the latter uncertainty corresponds to a total error budget of the order of 0.02°.

For the spinning superparticle we construct the pull-back of the world-line path integral to super moduli space in the Hamiltonian formulation. We describe the underlying geometric decomposition of super moduli space. Algebraically, this gives a realization of the cyclic complex. The resulting space-time action is classically equivalent to Yang-Mills theory up to boundary terms and additional non-local interactions.

We use the dispersion measure (DM) of localised Fast Radio Bursts (FRBs) to constrain cosmological and host galaxy parameters using simulation-based inference (SBI) for the first time. By simulating the large-scale structure of the electron density with the Generator for Large-Scale Structure (GLASS), we generate log-normal realisations of the free electron density field, accurately capturing the correlations between different FRBs. For the host galaxy contribution, we rigorously test various models, including log-normal, truncated Gaussian and Gamma distributions, while modelling the Milky Way component using pulsar data. Through these simulations, we employ the truncated sequential neural posterior estimation method to obtain the posterior. Using current observational data, we successfully recover the amplitude of the DM-redshift relation, consistent with Planck, while also fitting both the mean host contribution and its shape. Notably, we find no clear preference for a specific model of the host galaxy contribution. Although SBI may not yet be strictly necessary for FRB inference, this work lays the groundwork for the future, as the increasing volume of FRB data will demand precise modelling of both the host and large-scale structure components. Our modular simulation pipeline offers flexibility, allowing for easy integration of improved models as they become available, ensuring scalability and adaptability for upcoming analyses using FRBs. The pipeline is made publicly available under github.com/koustav-konar/FastNeuralBurst.

We propose heavy axions as a natural superheavy dark matter candidate in string theory, with the relic density of dark matter originating in quantum fluctuations during cosmic inflation. String theory is well known for the possibility of having tens to hundreds of axionlike particles—the axiverse. Moduli stabilization generates high-scale masses for many of these, placing them naturally in the "superheavy" regime of particle physics. We consider moduli stabilization in the Kachru-Kallosh-Linde-Trivedi framework, featuring a single volume modulus and <inline-formula><mml:math><mml:msub><mml:mi>C</mml:mi><mml:mn>4</mml:mn></mml:msub></mml:math></inline-formula> axion, and a fiducial inflation model minimally coupled to the volume modulus. We demonstrate that both the volume modulus and the axion can be abundantly produced through gravitational particle production. The former is unstable and readily decays to Standard Model particles while the latter (the axion) can be stable and survives to constitute the present day dark matter.

Emergent cooperative functionality in active matter systems plays a crucial role in various applications of active swarms, ranging from pollutant foraging and collective threat detection to tissue embolization. In nature, animals like bats and whales use acoustic signals to communicate and enhance their evolutionary competitiveness. Here, we show that information exchange by acoustic waves between active agents creates a large variety of multifunctional structures. In our realization of collective swarms, each unit is equipped with an acoustic emitter and a detector. The swarmers respond to the resulting acoustic field by adjusting their emission frequency and migrating toward the strongest signal. We find self-organized structures with different morphology, including snakelike self-propelled entities, localized aggregates, and spinning rings. These collective swarms exhibit emergent functionalities, such as phenotype robustness, collective decision making, and environmental sensing. For instance, the collectives show self-regeneration after strong distortion, allowing them to penetrate through narrow constrictions. Additionally, they exhibit a population-scale perception of reflecting objects and a collective response to acoustic control inputs. Our results provide insights into fundamental organization mechanisms in information-exchanging swarms. They may inspire design principles for technical implementations in the form of acoustically or electromagnetically communicating microrobotic swarms capable of performing complex tasks and concerting collective responses to external cues.

We apply the framework of Vlasov perturbation theory (<inline-formula><mml:math><mml:mrow><mml:mi>VPT</mml:mi></mml:mrow></mml:math></inline-formula>) to the two-loop matter power spectrum within <inline-formula><mml:math><mml:mi>Λ</mml:mi></mml:math></inline-formula> cold dark matter cosmologies. The main difference to standard perturbation theory (SPT) arises from taking the velocity dispersion tensor into account, and the resulting screening of the backreaction of UV modes renders loop integrals cutoff independent. <inline-formula><mml:math><mml:mrow><mml:mi>VPT</mml:mi></mml:mrow></mml:math></inline-formula> is informed about nonperturbative small-scale dynamics via the average value of the dispersion generated by shell-crossing, which impacts the evolution of perturbations on weakly nonlinear scales. When using an average dispersion from halo models, the <inline-formula><mml:math><mml:mrow><mml:mi>VPT</mml:mi></mml:mrow></mml:math></inline-formula> power spectrum agrees with the one from the simulation, up to differences from missing three-loop contributions. Alternatively, treating the average dispersion as a free parameter we find a remarkably stable prediction of the matter power spectrum from collisionless dynamics at percent level for a wide range of the dispersion scale. We quantify the impact of truncating the Vlasov hierarchy for the cumulants of the phase-space distribution function, finding that the two-loop matter power spectrum is robust to neglecting third and higher cumulants. Finally, we introduce and validate a simplified fast scheme fast <inline-formula><mml:math><mml:mrow><mml:mi>VPT</mml:mi></mml:mrow></mml:math></inline-formula> that can be easily incorporated into existing codes and is as numerically efficient as SPT.

The Min protein system prevents abnormal cell division in bacteria by forming oscillatory patterns between cell poles. However, predicting the protein concentrations at which oscillations start and whether cells can maintain them under physiological perturbations remains challenging. Here we show that dynamic pattern formation is robust across a wide range of Min protein levels and variations in the growth physiology using genetically engineered Escherichia coli strains. We modulate the expression of minCD and minE under fast- and slow-growth conditions and build a MinD versus MinE phase diagram that reveals dynamic patterns, including travelling and standing waves. We found that the natural expression level of Min proteins is resource-optimal and robust to changes in protein concentration. In addition, we observed an invariant wavelength of dynamic Min patterns across the phase diagram. We explain the experimental findings quantitatively with biophysical theory based on reaction–diffusion models that consider the switching of MinE between its latent and active states, indicating its essential role as a robustness module for Min oscillation in vivo. Our results underline the potential of integrating quantitative cell physiology and biophysical modelling to understand the fundamental mechanisms controlling cell division machinery, and they offer insights applicable to other biological processes.

Electroweakly interacting stable spin-1 particle in the (1-10) TeV mass range can be a dark matter candidate with rich testability. In particular, one or even two gamma-ray line-like features are expected to be a smoking-gun signature for indirect detection in this scenario. The presence of large Sudakov logarithmic corrections, though, significantly complicates the theoretical prediction of the gamma-ray spectrum. We resum these corrections at the next-to-leading-log (NLL) accuracy using Soft-Collinear Effective field Theory (SCET). Rather interestingly, we find that the LL- and NLL-resummed endpoint spectra for this model are, up to an overall factor, identical to already existing calculations in the contexts of spin-0 and spin-1/2 (i.e. wino-like) scenarios. We discuss how this non-trivial "exact universality" irrespective of DM spin at these accuracies comes about despite the completely different SCET operator bases. Our resummations allow us to reduce the uncertainty, demonstrated in the energy spectrum with distinctive two peaks from annihilations into γγ, Zγ channel and a photon with Z ₂-even extra heavy neutral boson Z ^'. We discuss the prospect of improving accuracy further, which is crucial for the heavier DM mass region and realistic resolution in future gamma-ray observations.

Context. Intermediate neutron-capture processes are thought to occur in stellar environments where protons are ingested into a hot helium-burning convective region. It has been shown that proton ingestion episodes can happen in the formation of hot-subdwarf stars, and that neutron-capture processes are possible in those cases. Moreover, some helium-rich hot subdwarfs display extraordinarily high abundances of heavy elements such as Zr, Yr, and Pb on their surfaces. These elements can be produced by both slow and intermediate neutron-capture processes. Aims. We explore under which conditions neutron-capture processes can occur in late helium core flashes, that is, those occurring in the cores of stripped red-giant stars. We explore the dependence of such processes on the metallicity of the star, and how much the star is stripped before the He flash takes place. Methods. We computed evolutionary models through the helium core flash and the subsequent hydrogen ingestion episode in stripped red-giant stars. Stellar structure models were then used in post-processing to compute the detailed evolution of neutron-capture elements. Results. We find that for metallicities of 10^‑3 and below, neutron densities can be as high as 10¹⁵ cm^‑3 and intermediate neutron-capture processes occur in some of our models. The results depend very strongly on the H-envelope mass that survives after the stripping, which alters the nucleosynthesis during the flashes, and therefore the behavior of the convective motions. Interestingly, we find that computed abundances in some of our models closely match the element abundances up to tin observed for EC 22536-5304, the only well-studied star for which the hot-flasher scenario assumed in our models is the most likely evolutionary path. Conclusions. Intermediate neutron-capture processes can occur in the He-core flash experienced by the cores of some stripped red giants, and this might be connected to the abundances of heavy elements observed in some helium-rich hot-subdwarf stars. The agreement between the observed abundances in EC 22536-5304 and those of our models offers support to our nucleosynthesis calculations. Moreover, if confirmed, the idea that heavy element abundances retain signatures of the different evolutionary channels opens the possibility that heavy element abundances in iHe-sdOB stars can be used to infer their evolutionary origin.

The relativistic <mml:math><mml:msub><mml:mrow><mml:mi>V</mml:mi></mml:mrow><mml:mrow><mml:mrow><mml:mi>low</mml:mi></mml:mrow><mml:mspace></mml:mspace><mml:mi>k</mml:mi></mml:mrow></mml:msub></mml:math> is developed from a renormalization group method for the first time, to provide softened NN interactions for relativistic <mml:math><mml:mi>a</mml:mi><mml:mi>b</mml:mi><mml:mspace></mml:mspace><mml:mi>i</mml:mi><mml:mi>n</mml:mi><mml:mi>i</mml:mi><mml:mi>t</mml:mi><mml:mi>i</mml:mi><mml:mi>o</mml:mi></mml:math> calculations. Starting from a given bare NN interaction, the renormalization group method eliminates the repulsive core while keeping the low-energy on-shell T-matrix and, consequently, the two-body observables unchanged. We derive the relativistic <mml:math><mml:msub><mml:mrow><mml:mi>V</mml:mi></mml:mrow><mml:mrow><mml:mrow><mml:mi>low</mml:mi></mml:mrow><mml:mspace></mml:mspace><mml:mi>k</mml:mi></mml:mrow></mml:msub></mml:math> interactions from the relativistic Bonn NN interactions across a wide range of cutoffs and study nuclear matter using the relativistic Brueckner-Hartree-Fock theory in the full Dirac space. Our results demonstrate that the resulting relativistic <mml:math><mml:msub><mml:mrow><mml:mi>V</mml:mi></mml:mrow><mml:mrow><mml:mrow><mml:mi>low</mml:mi></mml:mrow><mml:mspace></mml:mspace><mml:mi>k</mml:mi></mml:mrow></mml:msub></mml:math> interactions provide a proper description of nuclear saturation, exhibiting only mild cutoff dependence. Therefore, the relativistic <mml:math><mml:msub><mml:mrow><mml:mi>V</mml:mi></mml:mrow><mml:mrow><mml:mrow><mml:mi>low</mml:mi></mml:mrow><mml:mspace></mml:mspace><mml:mi>k</mml:mi></mml:mrow></mml:msub></mml:math> shows promise for providing reliable softened NN interactions for future relativistic <mml:math><mml:mi>a</mml:mi><mml:mi>b</mml:mi><mml:mspace></mml:mspace><mml:mi>i</mml:mi><mml:mi>n</mml:mi><mml:mi>i</mml:mi><mml:mi>t</mml:mi><mml:mi>i</mml:mi><mml:mi>o</mml:mi></mml:math> calculations of finite nuclei.

Context. The multitude of different architectures found for evolved exoplanet systems are in all likelihood set during the initial planet-formation phase in the circumstellar disk. To understand this process, we have to study the earliest phases of planet formation. Aims. Complex sub-structures, believed to be driven by embedded planets, have been detected in a significant portion of the disks observed at high angular resolution. We aim to extend the sample of such disks to low stellar masses and to connect the disk morphology to the expected proto-planet properties. Methods. In this study, we used VLT/SPHERE to obtain resolved images on the scale of ∼10 au of the circumstellar disk in the 2MASSJ16120668-3010270 system in polarized scattered light. We searched for the thermal radiation of recently formed gas giants embedded in the disk. Additionally, we used VLT/XSHOOTER to obtain the stellar properties in the system. Results. We resolve the disk in the 2MASSJ16120668-3010270 system for the first time in scattered near-infrared light and reveal an exceptionally structured disk. We find an inner disk (reaching out to 40 au) with two spiral arms, separated by a gap from an outer ring extending to 115 au. By comparison with our own model and hydrodynamic models from the literature, we find that these structures are consistent with the presence of an embedded gas giant with a mass range between 0.1 M_Jup and 5 M_Jup depending on the employed model and their underlying assumptions. Our SPHERE observations find a tentative candidate point source within the disk gap, the brightness of which would be consistent with this mass range if it indeed traces thermal emission by an embedded planet. This interpretation is somewhat strengthened by the proximity of this signal to compact millimeter continuum emission in the disk gap, which may trace circumplanetary material. It is, however, unclear if this tentative companion candidate could be responsible for the observed disk gap size, given its close proximity to the inner disk. Generally, our VLT/SPHERE observations set an upper limit of ∼5 M_Jup in the disk gap (∼0.2"‑0.5"), consistently with our modeling results. The 2MASSJ16120668-3010270 system is one of only a few systems that shows this exceptional morphology of spiral arms located inside a scattered light gap and ring. We speculate that this may have to do with a higher disk viscosity compared with other systems such as PDS 70. If planets in the disk are confirmed, 2MASSJ16120668-3010270 will become a prime laboratory for the study of planet-disk interaction. ★Based on observations made with ESO telescopes at the La Silla Paranal Observatory under program IDs 111.255B.001, 1104.C-0415(D) and 109.23BC.001.

We apply population synthesis techniques to analyze TYPHOON long slit spectra of the starburst barred spiral galaxy M83. The analysis covers a central square of 5' side length. We determine the spatial distribution of dust through the analysis of reddening and extinction, together with star formation rates, ages, and metallicities of young and old stellar populations. For the first time, a spatial one-to-one comparison of metallicities derived from full spectral fitting techniques with those obtained from individual young stellar probes has been carried out. The comparison with blue supergiant stars, young massive star clusters, and super star clusters shows a high degree of concordance when wavelength coverage in the B band is available. The metallicity of the young population is supersolar and does not show a radial metallicity gradient along the investigated part of the disk, in agreement with our chemical evolution model. However, a notable decrease in metallicity is observed in a tightly confined region at the galaxy center, coinciding with circumnuclear orbits. We attribute this to matter infall either from the circumgalactic medium, a dwarf galaxy interloper, or, alternatively, to active-galactic-nucleus-interrupted chemical evolution. We confirm the presence of a dust cavity with a diameter of 260 pc close to the galaxy center. Dust absorption and molecular CO emission are spatially well correlated. We find an anticorrelation between R_V, the ratio of dust attenuation to reddening, and the emission strength of molecular species present in photodissociation regions. We confirm our results by using alternative fitting algorithms and stellar libraries.

At any given scale, 3$\times$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 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 \verb|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.

LiteBIRD, the Lite (Light) satellite for the study of $B$-mode polarization and Inflation from cosmic background Radiation Detection, is a space mission focused on primordial cosmology and fundamental physics. In this paper, we present the LiteBIRD Simulation Framework (LBS), a Python package designed for the implementation of pipelines that model the outputs of the data acquisition process from the three instruments on the LiteBIRD spacecraft: LFT (Low-Frequency Telescope), MFT (Mid-Frequency Telescope), and HFT (High-Frequency Telescope). LBS provides several modules to simulate the scanning strategy of the telescopes, the measurement of realistic polarized radiation coming from the sky (including the Cosmic Microwave Background itself, the Solar and Kinematic dipole, and the diffuse foregrounds emitted by the Galaxy), the generation of instrumental noise and the effect of systematic errors, like pointing wobbling, non-idealities in the Half-Wave Plate, et cetera. Additionally, we present the implementation of a simple but complete pipeline that showcases the main features of LBS. We also discuss how we ensured that LBS lets people develop pipelines whose results are accurate and reproducible. A full end-to-end pipeline has been developed using LBS to characterize the scientific performance of the LiteBIRD experiment. This pipeline and the results of the first simulation run are presented in Puglisi et al. (2025).

Axion-like particles (ALPs) are well-motivated examples of light, weakly coupled particles in theories beyond the Standard Model. In this work, we study long-lived ALPs coupled exclusively to leptons in the mass range between $2 m_e$ and $m_τ- m_e$. For anarchic flavor structure the leptophilic ALP production in tau decays or from ALP-tau bremsstrahlung is enhanced thanks to derivative couplings of the ALP and can surpass production from electron and muon channels, especially for ALPs heavier than $m_μ$. Using past data from high-energy fixed-target experiments such as CHARM and BEBC we place new constraints on the ALP decay constant $f_a$, reaching scales as high as $\mathcal{O}(10^8)$~GeV in lepton-flavor-violating channels and $f_a \sim \mathcal{O}(10^2)$~GeV in lepton-flavor-conserving ones. We also present projections for the event-rate sensitivity of current and future detectors to ALPs produced at the Fermilab Main Injector, the CERN SPS, and in the forward direction of the LHC. We show that SHiP will be sensitive to $f_a$ values that are over an order of magnitude above the existing constraints.

Dark objects streaming into the solar system can be probed using gravitational wave (GW) experiments through the perturbations that they would induce on the detector test masses. In this work, we study the detectability of the resulting gravitational signal for a number of current and future GW observatories. Dark matter in the form of clumps or primordial black holes with masses in the range $10^7$-$10^{11}\,\rm{g}$ can be detected with the proposed DECIGO experiment.

The dust-to-gas ratio in the protoplanetary disk, which is likely imprinted into the host star metallicity, is a property that plays a crucial role during planet formation. We aim at constraining planet formation and evolution processes by statistically analysing planetary systems generated by the Generation III Bern model, comparing with the correlations derived from observational samples. Using synthetic planets biased to observational completeness, we find that (1) the occurrence rates of large giant planets and Neptune-size planets are positively correlated with [Fe/H], while small sub-Earths exhibit an anti-correlation. In between, for sub-Neptune and super-Earth, the occurrence rate first increases and then decreases with increasing [Fe/H] with an inflection point at 0.1 dex. (2) Planets with orbital periods shorter than ten days are more likely to be found around stars with higher metallicity, and this tendency weakens with increasing planet radius. (3) Both giant planets and small planets exhibit a positive correlation between the eccentricity and [Fe/H], which could be explained by the self-excitation and perturbation of outer giant planets. (4) The radius valley deepens and becomes more prominent with increasing [Fe/H], accompanied by a lower super-Earth-to-sub-Neptune ratio. Furthermore, the average radius of the planets above the valley increases with [Fe/H]. Our nominal model successfully reproduces many observed correlations with stellar metallicity, supporting the description of physical processes and parameters included in the Bern model. However, the dependences of orbital eccentricity and period on [Fe/H] predicted by the synthetic population is however significantly weaker than observed. This discrepancy suggests that long-term dynamical interactions between planets, along with the impact of binaries/companions, can drive the system towards a dynamically hotter state.

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.

It is shown that the generation of magnetic islands by pressure-gradient-driven turbulence is common across a wide range of conditions. The interaction among the turbulence, the magnetic island, and other large scale structures, namely, the zonal flow and the zonal current, largely determines the dynamics of the overall system. The turbulence takes a background role, providing energy to the large-scale structures, without influencing their evolution directly. It is found that the growth of the zonal current is linearly related to that of the magnetic island, while the zonal flow has a strongly sheared region where the island has its maximum radial extension. The zonal current is found to slow down the formation of large-scale magnetic islands, while the zonal flow is needed to have the system move its energy to larger and larger scales. The driving instability in the system is the fluid kinetic ballooning mode (KBM) instability at high <inline-formula> <mml:math><mml:mi>β</mml:mi></mml:math></inline-formula>, while the tearing mode is kept stable. The formation of magnetic-island-like structures at the spatial scale of the fluid KBM instability is observed quite early in the non-linear phase for most cases studied, and a slow coalescence process evolves the magnetic structures toward larger and larger scales. Cases, which did neither show this coalescence process nor show the formation of the small scale island-like structures, were seen to have narrower mode structures for comparable instability growth rates, which was achieved by varying the magnetic shear. The islands often end up exceeding the radial box size late in the non-linear phase, showing unbounded growth. The impact on the pressure profile of turbulence driven magnetic islands is not trivial, showing flattening of the pressure profile only far from the resonance, where the zonal flow is weaker, and the appearance of said flattening is slow, after the island has reached a sufficiently large size, when compared with collisional time scales.

The intracluster medium (ICM), composed of hot plasma, dominates the baryonic content of galaxy clusters and is primarily observable in X-rays. Its thermodynamic properties, pressure, temperature, entropy, and electron density, offer crucial insight into the physical processes shaping clusters, from accretion and mergers to radiative cooling and feedback. We investigate the thermodynamic properties of galaxy clusters in the Simulating the LOcal Web (SLOW) constrained simulations, which reproduce the observed large-scale structure of the local Universe. We assess how well these simulations reproduce observed ICM profiles and explore the connection between cluster formation history and core classification. Three-dimensional thermodynamic profiles are extracted and compared to deprojected X-ray and Sunyaev - Zel'dovich (SZ) data for local clusters classified as solid cool-core (SCC), weakly cool-core (WCC), and non-cool-core (NCC) systems. We also examine the mass assembly history of the simulated counterparts to link their formation to present-day ICM properties. The simulations reproduce global thermodynamic profiles for clusters such as Perseus, Coma, A85, A119, A1644, A2029, A3158, and A3266. Moreover, they show that CC clusters typically assemble their mass earlier, while NCC systems grow through more extended, late-time merger-driven histories. WCC clusters show intermediate behavior, suggesting an evolutionary transition. Our results demonstrate that constrained simulations provide a powerful tool for linking cluster formation history to present-day ICM properties and point to possible refinements in subgrid physics as well as in resolution that could improve the agreement in cluster core regions.

We investigate the possibility that the high-energy neutrino flux observed from the Seyfert galaxy NGC 1068 originates from dark matter annihilations within the density spike surrounding the supermassive black hole at its center. The comparatively lower gamma-ray flux is attributed to a dark sector that couples predominantly to Standard Model neutrinos. To explain the absence of a corresponding neutrino signal from the center of the Milky Way, we propose two scenarios: (i) the disruption of the dark matter spike at the Milky Way center due to stellar heating, or (ii) the annihilation into a dark scalar that decays exclusively into neutrinos, with a decay length longer than the size of the Milky Way but shorter than the distance from Earth to NGC 1068.

Context. Anomalous Cepheids (ACs) are pulsating variable stars, and are less studied compared to the well-known Classical Cepheids (CCs) and RR Lyrae stars. The ACs are metal poor ([Fe/H] < 1.5) and follow distinct period-luminosity (PL) and period-Wesenheit (PW) relations that can be used for distance measurements, and they can pulsate in the fundamental (F) and first overtone (1O) modes. Aims. Our goal is to evaluate the precision and accuracy of distances obtained via PL and PW relations of ACs and thus to assess if they could be used to establish a cosmic distance scale independent from CCs. To this aim, we derived new, precise PL and PW relations for the F mode, the 1O mode, and, for the first time, the combined F+1O mode ACs in the Magellanic Clouds. We investigated the wavelength dependence of these relations and applied them to calculate the distances of various stellar systems in the Local Group hosting ACs, as well as to confirm the classification of these variable stars. Methods. We analyzed near-infrared (NIR) time series photometry in the Y, J, and K_s bands for about 200 ACs in the Magellanic Clouds acquired during 2009–2018 in the context of the VISTA survey of the Magellanic Clouds system (VMC), a European Southern Observatory public survey. The VMC NIR photometry was complemented with optical data from Gaia DR3 and the Optical Gravitational Lensing Experiment IV survey, which also provided the identification, periods, and pulsation mode for the investigated ACs. Custom templates generated from our best light curves were used to derive precise intensity-averaged mean magnitudes for 118 and 75 ACs in the Large (LMC) and Small Magellanic Clouds (SMC), respectively. Results. Optical and NIR mean magnitudes were used to derive multiband PL and PW relations, which were calibrated with the geometric distance modulus to the LMC based on eclipsing binaries. We investigated the dependence of PL relations on wavelength, finding that slopes increase and dispersion decreases when going from optical to NIR bands. We calculated the LMC distance modulus through calibrated AC PW relations in the Milky Way using Gaia parallaxes, the LMC-SMC relative distance modulus, and we confirmed the AC nature of a few new pulsators in Galactic globular clusters. We derived a distance modulus for the Draco dwarf spheroidal galaxy of 19.425 ± 0.048 mag, which is in agreement with recent literature determinations, but a discrepancy of 0.1 mag with RR Lyrae-based distance hints at possible metallicity effects on the AC PL and PW relations. Future spectroscopic surveys and Gaia DR4 will refine the AC distance scale and assess metallicity effects on PLRs and PWRs.

Collective neutrino flavor conversions in core-collapse supernovae (SNe) begin with instabilities, initially triggered when the dominant $ν_e$ outflow concurs with a small flux of antineutrinos with the opposite lepton number, with $\overlineν_e$ dominating over $\overlineν_μ$. When these "flipped" neutrinos emerge in the energy-integrated angular distribution (angular crossing), they initiate a fast instability. However, before such conditions arise, spectral crossings typically appear within $20~\mathrm{ms}$ of collapse, i.e., local spectral excesses of $\overlineν_e$ over $\overlineν_μ$ along some direction. Therefore, post-processing SN simulations cannot consistently capture later fast instabilities because the early slow ones have already altered the conditions.

Context. Ultra-diffuse galaxies (UDGs) are an intriguing population of galaxies. Despite their dwarf-like stellar masses and low surface brightness, they have large half-light radii and exhibit a diverse range of globular cluster (GC) populations. Some UDGs host many GCs while others have none, raising questions about the conditions under which star clusters form in dwarf galaxies. GAMA 526784, an isolated UDG with both an old stellar body and an extended star-forming front, including many young star clusters, provides an exceptional case to explore the link between UDG evolution and star cluster formation. Aims. This study investigates the stellar populations, star clusters, ionised gas properties, and kinematics of GAMA 526784, focusing on the galaxy's potential to form massive GCs and its connection to broader UDG formation scenarios. Methods. Imaging from HST and Subaru/HSC, alongside MUSE spectroscopy, were used to analyse the galaxy's morphology, chemical composition, and kinematics. A combination of SED fitting and full spectral fitting was applied. Results. GAMA 526784's central stellar body exhibits a low-metallicity ([M/H] ∼‑1.0 dex) and an old age (t_M ∼9.9 Gyr), indicative of a quiescent core. The outskirts are much younger (t_M ∼0.9 Gyr), but slightly more metal-poor ([M/H] ∼‑1.2 dex). The stellar kinematics show low velocity dispersions (∼10 km s^‑1) and a coherent rotational field, while the ionised gas exhibits higher dispersions (reaching ∼50 km s^‑1), a misaligned rotation axis (∼20^∘) and localised star formation, what could be suggestive of a recent interaction. The young star clusters span ages of 8‑11 Myr and masses of log(M_⋆/M_⊙) ∼5.0, while the old GC candidates have ∼9 Gyr and stellar masses of log(M_⋆/M_⊙) ∼5.5. Conclusions. GAMA 526784's properties point to interactions that triggered localised star formation, leading to the formation of young star clusters. Future observations of its molecular and neutral gas content will help assess its environment, the trigger of this star-forming episode, and explore its potential to sustain star formation.

Despite the 3D nature of core-collapse supernovae (CCSNe), simulations in spherical symmetry (1D) play an important role to study large model sets for the progenitor-remnant connection, explosion properties, remnant masses, and CCSN nucleosynthesis. To trigger explosions in 1D, various numerical recipes have been applied, mostly with gross simplifications of the complex microphysics governing stellar core collapse, the formation of the compact remnant, and the mechanism of the explosion. Here, we investigate the two most popular treatments, piston-driven and thermal-bomb explosions, in comparison to 1D explosions powered by a parametric neutrino engine in the P-HOTB code. For this comparison, we calculate CCSNe for eight stars and evolution times up to <inline-formula><tex-math>$10^4$</tex-math></inline-formula> s, targeting the same progenitor-specific explosion energies as obtained by the neutrino-engine results. Otherwise, we employ widely used ('classic') modelling assumptions, and alternatively to the standard contraction–expansion trajectory for pistons, we also test suitably selected Lagrangian mass shells adopted from the neutrino-driven explosions as 'special trajectories'. Although the <inline-formula><tex-math>$^{56}$</tex-math></inline-formula>Ni production agrees within roughly a factor of two between the different explosion triggers, neither piston nor thermal bombs can reproduce the correlation of <inline-formula><tex-math>$^{56}$</tex-math></inline-formula>Ni yields and explosion energies found in neutrino-driven explosions. This shortcoming as well as the problem of massive fallback witnessed in classical piston models, which diminishes or extinguishes the ejected nickel, can be largely cured by the special trajectories. These and the choice of the explosion energies, however, make the modelling dependent on pre-existing neutrino-driven explosion results.

We assess the computational feasibility of end-to-end Bayesian analysis of the JAXA-led LiteBIRD experiment by analysing simulated time ordered data (TOD) for a subset of detectors through the Cosmoglobe and Commander3 framework. The data volume for the simulated TOD is 1.55 TB, or 470 GB after Huffman compression. From this we estimate a total data volume of 238 TB for the full three year mission, or 70 TB after Huffman compression. We further estimate the running time for one Gibbs sample, from TOD to cosmological parameters, to be approximately 3000 CPU hours. The current simulations are based on an ideal instrument model, only including correlated 1/f noise. Future work will consider realistic systematics with full end-to-end error propagation. We conclude that these requirements are well within capabilities of future high-performance computing systems.

A hallmark of the computational campaign in nuclear and particle physics is the lattice-gauge-theory program. It continues to enable theoretical predictions for a range of phenomena in nature from the underlying Standard Model. The emergence of a new computational paradigm based on quantum computing, therefore, can introduce further advances in this program. In particular, it is believed that quantum computing will make possible first-principles studies of matter at extreme densities, and in and out of equilibrium, hence improving our theoretical description of early universe, astrophysical environments, and high-energy particle collisions. Developing and advancing a quantum-computing based lattice-gauge-theory program, therefore, is a vibrant and fast-moving area of research in theoretical nuclear and particle physics. These lecture notes introduce the topic of quantum computing lattice gauge theories in a pedagogical manner, with an emphasis on theoretical and algorithmic aspects of the program, and on the most common approaches and practices, to keep the presentation focused and useful. Hamiltonian formulation of lattice gauge theories is introduced within the Kogut-Susskind framework, the notion of Hilbert space and physical states is discussed, and some elementary numerical methods for performing Hamiltonian simulations are discussed. Quantum-simulation preliminaries and digital quantum-computing basics are presented, which set the stage for concrete examples of gauge-theory quantum-circuit design and resource analysis. A step-by-step analysis is provided for a simpler Abelian gauge theory, and an overview of our current understanding of the quantum-computing cost of quantum chromodynamics is presented in the end. Examples and exercises augment the material, and reinforce the concepts and methods introduced throughout.

The XRISM Resolve X-ray spectrometer allows to gain detailed insight into gas motions of the intra cluster medium (ICM) of galaxy clusters. Current simulation studies focus mainly on statistical comparisons, making the comparison to the currently still small number of clusters difficult due to unknown selection effects. This study aims to bridge this gap, using simulated counterparts of Coma, Virgo, and Perseus from the SLOW constrained simulations. These clusters show excellent agreement in their properties and dynamical state with observations, thus providing an ideal testbed to understand the processes shaping the properties of the ICM. We find that the simulations match the order of the amount of turbulence for the three considered clusters, Coma being the most active, followed by Perseus, while Virgo is very relaxed. Typical turbulent velocities are a few $\approx100$ km s$^{-1}$, very close to observed values. The resulting turbulent pressure support is $\approx1\%$ for Virgo and $\approx 3-4\%$ for Perseus and Coma within the central $1-2\%$ of $R_{200}$. Compared to previous simulations and observations, measured velocities and turbulent pressure support are consistently lower, in line with XRISM findings, thus indicating the importance of selection effects.

We investigate the interaction between a shock-driven hot wind and a cold multicloud layer, for conditions commonly found in interstellar and circumgalactic gas. We present a method for identifying distinct clouds using a friends-of-friends algorithm. This approach unveils novel detailed information about individual clouds and their collective behaviour. By tracing the evolution of individual clouds, our method provides comprehensive descriptions of cloud morphology, including measures of the elongation and fractal dimension. Combining the kinematics and morphology of clouds, we refine previous models for drag and entrainment processes. Our by-cloud analysis allows to discern the dominant entrainment processes at different times. We find that after the initial shock passage, momentum transfer due to condensation becomes increasingly important, compared to ram pressure, which dominates at early times. We also find that internal motions within clouds act as an effective dynamic pressure that exceeds the thermal pressure by an order of magnitude. Our analysis shows how the highly efficient cooling of the warm mixed gas at temperatures <inline-formula><tex-math>$\sim 10^{5}$</tex-math></inline-formula> K is effectively balanced by the kinetic energy injected by the hot wind into the warm and cold phases via shocks and shear motions. Compression-driven condensation and turbulence dissipation maintain a multiphase outflow and can help explain the presence of dense gas in galaxy-scale winds. Finally, we show that applying our friends-of-friends analysis to H I-emitting gas and correcting for beam size and telescope sensitivity can explain two populations of H I clouds within the Milky-Way nuclear wind as structures pertaining to the same outflow.

In dense neutrino environments, the mean field of flavor coherence can develop instabilities. A necessary condition is that the flavor lepton number changes sign as a function of energy and/or angle. Whether such a crossing is also sufficient has been a longstanding question. We construct an explicit counterexample: a spectral crossing without accompanying flavor instability, with an even number of crossings being key. This failure is physically understood as Cherenkov-like emission of flavor waves. If flipped-lepton-number neutrinos never dominate among those kinematically allowed to decay, the waves cannot grow.

Metallicities of both gas and stars decline toward large radii in spiral galaxies, a trend known as the radial metallicity gradient. We quantify the evolution of the metallicity gradient in the Milky Way as traced by APOGEE red giants with age estimates from machine learning algorithms. Stars up to ages of ∼9 Gyr follow a similar relation between metallicity and Galactocentric radius. This constancy challenges current models of Galactic chemical evolution, which typically predict lower metallicities for older stellar populations. Our results favor an equilibrium scenario, in which the gas-phase gradient reaches a nearly constant normalization early in the disk lifetime. Using a fiducial choice of parameters, we demonstrate that one possible origin of this behavior is an outflow that more readily ejects gas from the interstellar medium (ISM) with increasing Galactocentric radius. A direct effect of the outflow is that baryons do not remain in the ISM for long, which causes the ratio of star formation to accretion, <inline-formula> <mml:math><mml:msub><mml:mrow><mml:mover><mml:mrow><mml:mo>Σ</mml:mo></mml:mrow><mml:mrow><mml:mo>̇</mml:mo></mml:mrow></mml:mover></mml:mrow><mml:mrow><mml:mo>⋆</mml:mo></mml:mrow></mml:msub><mml:mo>/</mml:mo><mml:msub><mml:mrow><mml:mover><mml:mrow><mml:mo>Σ</mml:mo></mml:mrow><mml:mrow><mml:mo>̇</mml:mo></mml:mrow></mml:mover></mml:mrow><mml:mrow><mml:mspace></mml:mspace><mml:mtext>in</mml:mtext><mml:mspace></mml:mspace></mml:mrow></mml:msub></mml:math> </inline-formula>, to quickly become constant. This ratio is closely related to the local equilibrium metallicity, since its numerator and denominator set the rates of metal production by stars and hydrogen gained through accretion, respectively. Building in a merger event results in a perturbation that evolves back toward the equilibrium state on ∼Gyr timescales. Under the equilibrium scenario, the radial metallicity gradient is not a consequence of the inside-out growth of the disk but instead reflects a trend of declining <inline-formula> <mml:math><mml:msub><mml:mrow><mml:mover><mml:mrow><mml:mo>Σ</mml:mo></mml:mrow><mml:mrow><mml:mo>̇</mml:mo></mml:mrow></mml:mover></mml:mrow><mml:mrow><mml:mo>⋆</mml:mo></mml:mrow></mml:msub><mml:mo>/</mml:mo><mml:msub><mml:mrow><mml:mover><mml:mrow><mml:mo>Σ</mml:mo></mml:mrow><mml:mrow><mml:mo>̇</mml:mo></mml:mrow></mml:mover></mml:mrow><mml:mrow><mml:mspace></mml:mspace><mml:mtext>in</mml:mtext><mml:mspace></mml:mspace></mml:mrow></mml:msub></mml:math> </inline-formula> with increasing Galactocentric radius.

The Standard Model Effective Field Theory (SMEFT) based on the unbroken gauge group $\text{SU(3)}_C\otimes\text{SU(2)}_L\otimes\text{U(1)}_Y$ and containing only particles of the Standard Model (SM) has developed in the last decade to a mature field. It is the framework to be used in the energy gap from scales sufficiently higher than the electroweak scale up to the lowest energy scale at which new particles show up. We summarize the present status of this theory with a particular emphasize on its role in the indirect search for new physics (NP). While flavour physics of both quarks and leptons is the main topic of our review, we also discuss electric dipole moments, anomalous magnetic moments $(g-2)_{μ,e}$, $Z$-pole observables, Higgs observables and high-$p_T$ scattering processes within the SMEFT. We group the observables into ten classes and list for each class the most relevant operators and the corresponding renormalization group equations (RGEs). We exhibit the correlations between different classes implied both by the operator mixing and the $\text{SU(2)}_L$ gauge symmetry. Our main goal is to provide an insight into the complicated operator structure of this framework which hopefully will facilitate the identification of valid ultraviolet completions behind possible anomalies observed in future data. Numerous colourful charts, and 85 tables, while representing rather complicated RG evolution from the NP scale down to the electroweak scale, beautify the involved SMEFT landscape. Over 950 references to the literature underline the importance and the popularity of this field. We discuss both top-down and bottom-up approaches as well as their interplay. This allows us eventually to present an atlas of different landscapes beyond the SM that includes heavy gauge bosons and scalars, vector-like quarks and leptons and leptoquarks.

Cosmic microwave background (CMB) photons are deflected by large-scale structure through gravitational lensing. This secondary effect introduces higher-order correlations in CMB anisotropies, which are used to reconstruct lensing deflections. This allows mapping of the integrated matter distribution along the line of sight, probing the growth of structure, and recovering an undistorted view of the last-scattering surface. Gravitational lensing has been measured by previous CMB experiments, with $\textit{Planck}$'s $42\,σ$ detection being the current best full-sky lensing map. We present an enhanced $\textit{LiteBIRD}$ lensing map by extending the CMB multipole range and including the minimum-variance estimation, leading to a $49$ to $58\,σ$ detection over $80\,\%$ of the sky, depending on the final complexity of polarized Galactic emission. The combination of $\textit{Planck}$ and $\textit{LiteBIRD}$ will be the best full-sky lensing map in the 2030s, providing a $72$ to $78\,σ$ detection over $80\,\%$ of the sky, almost doubling $\textit{Planck}$'s sensitivity. Finally, we explore different applications of the lensing map, including cosmological parameter estimation using a lensing-only likelihood and internal delensing, showing that the combination of both experiments leads to improved constraints. The combination of $\textit{Planck}$ + $\textit{LiteBIRD}$ will improve the $S_8$ constraint by a factor of 2 compared to $\textit{Planck}$, and $\textit{Planck}$ + $\textit{LiteBIRD}$ internal delensing will improve $\textit{LiteBIRD}$'s tensor-to-scalar ratio constraint by $6\,\%$. We have tested the robustness of our results against foreground models of different complexity, showing that a significant improvement remains even for the most complex foregrounds.

Galaxies whose images overlap in the focal plane of a telescope, commonly referred to as blends, are often located at different redshifts. Blending introduces a challenge to weak lensing cosmology probes, as such blends are subject to shear signals from multiple redshifts. This effect can be described by joining shear bias and redshift characterisation in the effective redshift distribution, $n_γ(z)$, which includes the response of apparent shapes of detected objects to shear of galaxies at redshift $z$. In this work, we propose a novel method to correct $n_γ(z)$ for redshift-mixed blending by emulating the shear response to neighbouring galaxies. Specifically, we design a ``half-sky-shearing'' simulation with HSC-Wide-like specifications, in which we extract the response of a detected object's measured ellipticity to shear of neighbouring galaxies among numerous galaxy pairs. We demonstrate the feasibility of accurately emulating these pairwise responses and validate the robustness of our approach under varying observing conditions and galaxy population uncertainties. We find that the effective redshift of sources at the high-redshift tail of the distribution is about 0.05 lower than expected when not modelling the effect. Given appropriately processed image simulations, our correction method can be readily incorporated into future cosmological analyses to mitigate this source of systematic error.

Baryonic feedback fundamentally alters the total matter distribution on small to intermediate cosmological scales, posing a significant challenge for contemporary cosmological analyses. Direct tracers of the baryon distribution are therefore key for unearthing cosmological information buried under astrophysical effects. Fast Radio Bursts (FRBs) have emerged as a novel and direct probe of baryons, tracing the integrated ionised electron density along the line-of-sight, quantified by the dispersion measure (DM). The scatter of the DM as a function of redshift provides insight into the lumpiness of the electron distribution and, consequently, baryonic feedback processes. Using a model calibrated to the \texttt{BAHAMAS} hydrodynamical simulation suite, we forward-model the statistical properties of the DM with redshift. Applying this model to approximately 100 localised FRBs, we constrain the governing feedback parameter, $\log T_\mathrm{AGN}$. Our findings represent the first measurement of baryonic feedback using FRBs, demonstrating a strong rejection of no-feedback scenarios at greater than $99.7\,\%$ confidence ($3σ$), depending on the FRB sample. We find that FRBs prefer fairly strong feedback, similar to other measurements of the baryon distribution, via the thermal and kinetic Sunyaev-Zel'dovich effect. The results are robust against sightline correlations and modelling assumptions. We emphasise the importance of accurate calibration of the host galaxy and Milky Way contributions to the DM. Furthermore, we discuss implications for future FRB surveys and necessary improvements to current models to ensure accurate fitting of upcoming data, particularly that from low-redshift FRBs.

Context. The stellar halos of low-mass galaxies (M_* ≤ 10¹⁰ M_⊙) are becoming objects of interest among the extragalactic community due to a recent set of observations with the capacity to detect such structures. Additionally, new and very-high-resolution cosmological simulations have been performed, enabling the study of this faint component in low-mass galaxies. The presence of stellar halos in low-mass systems could help shed light on our understanding of the assembly of low-mass observed galaxies and their evolution. It could also allow us to test whether the hierarchical model for the formation of structures is applicable at small scales. Aims. In this work, we aim to characterise the stellar halos of simulated low-mass galaxies and analyse their evolution and accretion history. Methods. We used a sample of 17 simulated low-mass galaxies from the Auriga Project with a stellar mass range from 3.28 × 10⁸ M_⊙ to 2.08 × 10¹⁰ M_⊙. These are cosmological magneto-hydrodynamical zoom-in simulations that have a very high resolution 5 × 10⁴ M_⊙ in dark matter (DM) mass and ∼6 × 10³ M_⊙ in baryonic mass. We defined the stellar halo as the stellar material located outside of an ellipsoid with semi-major axes equal to four times the half-light radius of each galaxy. We analysed the stellar halos of these galaxies and studied their formation channels. Results. We find that the inner regions of the stellar halo (between four and six times the half-light radius) are dominated by in situ material. For the less massive simulated dwarfs (M_* ≤ 4.54 × 10⁸ M_⊙), this dominance extends to all radii. We find that this in situ stellar halo is mostly formed in the inner regions of the galaxies and was subsequently ejected into the outskirts during interactions and merger events with satellite galaxies. In ∼50% of the galaxies, the stripped gas from satellite galaxies (likely mixed with the gas from the host dwarf) contributed to the formation of this in situ halo. The stellar halos of the galaxies more massive than M_* ≥ 1 × 10⁹ M_⊙ are dominated by the accreted component beyond six half-light radii. We find that the more massive dwarf galaxies (M_* ≥ 6.30 × 10⁹ M_⊙) accrete stellar material until later times (τ₉₀ ≈ 4.44 Gyr ago, with τ₉₀ as the formation time) than the less massive ones (τ₉₀ ≈ 8.17 Gyr ago). This has an impact on the formation time of the accreted stellar halos. These galaxies have between one and seven significant progenitors that contribute to the accreted component of these galaxies; however, there is no clear correlation between the amount of accreted mass of the galaxies and their number of significant progenitors.

We present the searches conducted with the Zwicky Transient Facility (ZTF) in response to S250206dm, a bona fide event with a false alarm rate of one in 25 years, detected by the International Gravitational Wave Network (IGWN). Although the event is significant, the nature of the compact objects involved remains unclear, with at least one likely neutron star. ZTF covered 68% of the localization region, though we did not identify any likely optical counterpart. We describe the ZTF strategy, potential candidates, and the observations that helped rule out candidates, including sources circulated by other collaborations. Similar to Ahumada et al. 2024, we perform a frequentist analysis, using simsurvey, as well as Bayesian analysis, using nimbus, to quantify the efficiency of our searches. We find that, given the nominal distance to this event of 373$\pm$104 Mpc, our efficiencies are above 10% for KNe brighter than $-17.5$ absolute magnitude. Assuming the optical counterpart known as kilonova (KN) lies within the ZTF footprint, our limits constrain the brightest end of the KN parameter space. Through dedicated radiative transfer simulations of KNe from binary neutron star (BNS) and black hole-neutron star (BHNS) mergers, we exclude parts of the BNS KN parameter space. Up to 35% of the models with high wind ejecta mass ($M_{\rm wind} \approx 0.13$ M$_{\odot}$) are ruled out when viewed face-on ($\cosθ_{\rm obs} = 1.0$). Finally, we present a joint analysis using the combined coverage from ZTF and the Gravitational Wave Multimessenger Dark Energy Camera Survey (GW-MMADS). The joint observations cover 73% of the localization region, and the combined efficiency has a stronger impact on rising and slowly fading models, allowing us to rule out 55% of the high-mass KN models viewed face-on.

Scattering amplitudes are expected to admit a factorised structure in special kinematic limits, such as the Regge, soft and collinear limits. However, less is known about the precise mechanisms through which factorisation of $n$-particle scattering amplitudes is realised at high perturbative orders, where more complex structures arise. Starting with the soft anomalous dimension, in this work we investigate the multi-particle collinear limits of massless amplitudes at three- and four-loop orders. Using colour conservation and rescaling symmetry, we show how strict collinear factorisation of multiple massless final-state coloured particles is realised, and provide results for the corresponding splitting amplitude soft anomalous dimensions. In particular, we demonstrate through four loops that the conditions on the structure of the soft anomalous dimension that are required by strict collinear factorisation in all two-particle collinear limits, are sufficient to guarantee such factorisation also in any multiple collinear limit. Then, assuming that strict collinear factorisation of massless partons holds also for amplitudes containing massive coloured particles, we derive new constraints on the soft anomalous dimension from multi-collinear limits.

Mean-field dynamo theory, describing the evolution of large-scale magnetic fields, has been the mainstay of theoretical interpretation of magnetism in astrophysical objects such as the Sun for several decades. More recently, three-dimensional magnetohydrodynamic simulations have reached a level of fidelity where they capture dynamo action self-consistently on local and global scales without resorting to parametrization of unresolved scales. Recent global simulations also capture many of the observed characteristics of solar and stellar large-scale magnetic fields and cycles. Successful explanation of the results of such simulations with corresponding mean-field models is a crucial validation step for mean-field dynamo theory. Here the connections between mean-field theory and current dynamo simulations are reviewed. These connections range from the numerical computation of turbulent transport coefficients to mean-field models of simulations, and their relevance to the solar dynamo. Finally, the most notable successes and current challenges in mean-field theoretical interpretations of simulations are summarized.

We present the first gamma-ray burst (GRB) host galaxy with a measured absorption line and electron temperature (T_e) based metallicity, using the temperature sensitive [O III]λ4363 auroral line detected in the JWST/NIRSpec spectrum of the host of GRB 050505 at redshift z = 4.28. We find that the metallicity of the cold interstellar gas, derived from the absorption lines in the GRB afterglow, of 12 + log(O/H)~7.7 is in reasonable agreement with the temperature-based emission line metallicity in the warm gas of the GRB host galaxy, which has values of 12 + log(O/H) = 7.80±0.19 and 7.96±0.21 for two common indicators. When using strong emission line diagnostics appropriate for high-z galaxies and sensitive to ionisation parameter, we find good agreement between the strong emission line metallicity and the other two methods. Our results imply that, for the host of GRB050505, mixing between the warm and the cold ISM along the line of sight to the GRB is efficient, and that GRB afterglow absorption lines can be a reliable tracer of the metallicity of the galaxy. If confirmed with a large sample, this suggest that metallicities determined via GRB afterglow spectroscopy can be used to trace cosmic chemical evolution to the earliest cosmic epochs and in galaxies far too faint for emission line spectroscopy, even for JWST.

We derive constraints on the neutrino mass using a variety of recent cosmological datasets, including DESI BAO, the full-shape analysis of the DESI matter power spectrum and the one-dimensional power spectrum of the Lyman-$α$ forest (P1D) from eBOSS quasars as well as the cosmic microwave background (CMB). The constraints are obtained in the frequentist formalism by constructing profile likelihoods and applying the Feldman-Cousins prescription to compute confidence intervals. This method avoids potential prior and volume effects that may arise in a comparable Bayesian analysis. Parabolic fits to the profiles allow one to distinguish changes in the upper limits from variations in the constraining power $σ$ of the different data combinations. We find that all profiles in the $Λ$CDM model are cut off by the $\sum m_ν\geq 0$ bound, meaning that the corresponding parabolas reach their minimum in the unphysical sector. The most stringent 95% C.L. upper limit is obtained by the combination of DESI DR2 BAO, Planck PR4 and CMB lensing at 53 meV, below the minimum of 59 meV set by the normal ordering. Extending $Λ$CDM to non-zero curvature and $w_0w_\mathrm{a}$CDM relaxes the constraints past 59 meV again, but only $w_0w_\mathrm{a}$CDM exhibits profiles with a minimum at a positive value. Using a combination of DESI DR1 full-shape, BBN and eBOSS Lyman-$α$ P1D, we successfully constrain the neutrino mass independently of the CMB. This combination yields $\sum m_ν\leq 285$ meV (95% C.L.). The addition of DESI full-shape or Lyman-$α$ P1D to CMB and DESI BAO results in small but noticeable improvement of the constraining power of the data. Lyman-$α$ free-streaming measurements especially improve the constraint. Since they are based on eBOSS data, this sets a promising precedent for upcoming DESI data.

Context. The nearest giant spiral, the Andromeda galaxy (M31), exhibits a kinematically hot stellar disc, a global star formation episode ∼2–4 Gyr ago, and conspicuous substructures in its stellar halo that are suggestive of a recent accretion event. Aims. Recent chemodynamical measurements in the M31 disc and inner halo can be used as additional constraints for N-body hydrodynamical simulations that successfully reproduce the disc age-velocity dispersion relation and star formation history as well as the morphology of the inner halo substructures. Methods. We combined an available N-body hydrodynamical simulation of a major merger (mass ratio 1:4) with a well-motivated chemical model to predict abundance distributions and gradients in the merger remnant at z = 0. We computed the projected phase space and the [M/H] distributions for the substructures in the M31 inner halo, namely, the Giant Stellar Stream (GSS) and the North-East (NE) and Western (W) shelves. We compared the chemodynamical properties of the simulated M31 remnant with recent measurements for the M31 stars in the inner halo substructures. Results. This major merger model predicts (i) multiple distinct components within each of the substructures; (ii) a high mean metallicity and large spread in the GSS and NE and W shelves, which explain various photometric and spectroscopic metallicity measurements; (iii) simulated phase space diagrams that qualitatively reproduce various features identified in the projected phase space of the substructures in published data from the Dark Energy Spectroscopic Instrument (DESI); (iv) a large distance spread in the GSS, as suggested by previous tip of the red giant branch measurements; and (v) phase space ridges caused by several wraps of the secondary as well as up-scattered main M31 disc stars that also have plausible counterparts in the observed phase spaces. Conclusions. These results provide further strong and independent arguments for a major satellite merger in M31 ∼3 Gyr ago and a coherent explanation for many of the observational results that make M31 appear so different from the Milky Way.

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.

We employ on-shell methods to construct scattering amplitudes and derive effective theories involving massive spin-3/2 fermions interacting with spin 0, 1 and 2 bosons. The four-point massive amplitudes are constructed using an all-line-transverse momentum shift, assuming that in the massless limit, three-point interactions are smooth and the Ward identity is satisfied. For a Majorana spin-3/2 fermion with mass $m_{3/2}$, we show that interactions with only spin 0 and massive spin-1 bosons do not lead to an effective theory valid up to a cutoff $Λ\gg m_{3/2}$ that is independent of particle masses. Instead, adding an interaction with a spin-2 graviton gives rise to four-point amplitudes with a Planck scale unitarity cutoff that reproduces well-known results from $N=1$ supergravity, such as $F$-term breaking with a complex scalar and $D$-term breaking with an additional massive photon. These bottom-up results are then extended to two Majorana spin-3/2 fermions where an interacting effective theory valid up to $Λ\gg m_{3/2}$ again requires the introduction of the spin-2 graviton. Unitarity up to the Planck scale is then achieved when the two Majorana spin-3/2 fermions have unequal masses, and necessarily couple to two massive spin-1 states corresponding to the spontaneous breaking of $N=2$ supergravity to $N=0$. Our results, obtained from the bottom-up and without any Lagrangian, imply that broken supergravity is the unique, effective theory involving interactions of massive spin-3/2 fermions valid up to a cutoff $Λ\gg m_{3/2}$ that does not depend on particle masses.

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.

We investigate the James Webb Space Telescope (JWST) MIRI MRS gas molecular content of an externally irradiated Herbig disk, the F-type XUE 10 source, in the context of the eXtreme UV Environments (XUE) program. XUE 10 belongs to the massive star cluster NGC 6357 (1.69 kpc), where it is exposed to an external far-ultraviolet (FUV) radiation $\approx$ 10$^3$ times stronger than in the Solar neighborhood. We modeled the molecular features in the mid-infrared spectrum with Local Thermodynamic Equilibrium (LTE) 0D slab models. We derived basic parameters of the stellar host from a VLT FORS2 optical spectrum using PHOENIX stellar templates. We detect bright CO2 gas with the first simultaneous detection (> 5$σ$) of four isotopologues (12CO2, 13CO2, 16O12C18O, 16O12C17O) in a protoplanetary disk. We also detect faint CO emission (2$σ$) and the HI Pf$α$ line (8$σ$). We also place strict upper limits on the water content, finding a total column density $\lesssim$ 10$^{18}$ cm$^{-2}$. The CO2 species trace low gas temperatures (300-370 K) with a range of column densities of 7.4 $\times$ 10$^{17}$ cm$^{-2}$ (16O12C17O)-1.3 $\times$ 10$^{20}$ cm$^{-2}$ (12CO2) in an equivalent emitting radius of 1.15 au. The emission of 13CO2 is likely affected by line optical depth effects. 16O12C18O and 16O12C17O abundances may be isotopically anomalous compared to the 16O/18O and 16O/17O ratios measured in the interstellar medium and the Solar System. We propose that the mid-infrared spectrum of XUE 10 is explained by H2O removal either via advection or strong photo-dissociation by stellar UV irradiation, and enhanced local CO2 gas-phase production. Outer disk truncation supports the observed CO2-H2O dichotomy. A CO2 vapor enrichment in 18O and 17O can be explained by means of external UV irradiation and early on (10$^{4-5}$ yr) delivery of isotopically anomalous water ice to the inner disk.

The X-SHYNE library is a homogeneous sample of 43 medium-resolution (R=8000) infrared (0.3-2.5um) spectra of young (<500Myr), low-mass (<20Mjup), and cold (Teff=600-2000K) isolated brown dwarfs and wide-separation companions observed with the VLT/X-Shooter instrument. To characterize our targets, we performed a global comparative analysis. We first applied a semi-empirical approach. By refining their age and bolometric luminosity, we derived key atmospheric and physical properties, such as Teff, mass, surface gravity (g), and radius, using the evolutionary model COND03. These results were then compared with the results from a synthetic analysis based on three self-consistent atmospheric models. To compare our spectra with these grids we used the Bayesian inference code ForMoSA. We found similar Lbol estimates between both approaches, but an underestimated Teff from the cloudy models, likely due to a lack of absorbers that could dominate the J and H bands of early L. We also observed a discrepancy in the log(g) estimates, which are dispersed between 3.5 and 5.5 dex for mid-L objects. We interpreted this as a bias caused by a range of rotational velocities leading to cloud migration toward equatorial latitudes, combined with a variety of viewing angles that result in different observed atmospheric properties (cloud column densities, atmospheric pressures, etc.). Finally, while providing robust estimates of [M/H] and C/O for individual objects remains challenging, the X-SHYNE library globally suggests solar values, which are consistent with a formation via stellar formation mechanisms. This study highlights the strength of homogeneous datasets in performing comparative analyses, reducing the impact of systematics, and ensuring robust conclusions while avoiding over-interpretation.

We present a detailed kinematic study of a sample of 32 massive (9.5≤ log(M_*/{M_{⊙}})≤10.9) main-sequence star-forming galaxies (MS SFGs) at 4<z<6 from the ALMA-CRISTAL program. The data consist of deep (up to 15hr observing time per target), high-resolution (∼1kpc) ALMA observations of the [CII]158μm line emission. This data set enables the first systematic kpc-scale characterisation of the kinematics nature of typical massive SFGs at these epochs. We find that ∼50% of the sample are disk-like, with a number of galaxies located in systems of multiple components. Kinematic modelling reveals these main sequence disks exhibit high-velocity dispersions (σ_0), with a median disk velocity dispersion of ∼70{kms^{-1}} and V_{rot}/σ_0∼2, and consistent with dominant gravity driving. The elevated disk dispersions are in line with the predicted evolution based on Toomre theory and the extrapolated trends from z∼0-2.5 MS star-forming disks. The inferred dark matter (DM) mass fraction within the effective radius f_{DM}(<R_{e}) for the disk systems decreases with the central baryonic mass surface density, and is consistent with the trend reported by kinematic studies at z≲3; roughly half the disks have f_{DM}(<R_{e})≲30%. The CRISTAL sample of massive MS SFGs provides a reference of the kinematics of a representative population and extends the view onto typical galaxies beyond previous kpc-scale studies at z≲3.

We systematically extend the framework of galaxy bias renormalization to two-loop order. For the minimal complete basis of 29 deterministic bias operators up to fifth order in the density field and at leading order in gradient expansion we explicitly work out one- and two-loop renormalization. The latter is provided in terms of double-hard limits of bias kernels, which we find to depend on only one function of the ratio of the loop momenta. After including stochasticity in terms of composite operator renormalization, we apply the framework to the two-loop power spectrum of biased tracers and provide a simple result suitable for numerical evaluation. In addition, we work out one- and two-loop renormalization group equations (RGE) for deterministic bias coefficients related to bias operators constructed from a smoothed density field, generalizing previous works. We identify a linear combination of bias operators with enhanced UV sensitivity, related to a positive eigenvalue of the RGE. Finally, we present an analogy with the RGE as used in quantum field theory, suggesting that a resummation of large logarithms as employed in the latter may also yield useful applications in the study of large-scale galaxy bias.

Supergiant B[e] (sgB[e]) stars are exceptionally rare objects, with only a handful of confirmed examples in the Milky Way. The evolutionary pathways leading to the sgB[e] phase remain largely debated, highlighting the need for additional observations. The sgB[e] star Wd1-9, located in the massive cluster Westerlund 1 (Wd1), is enshrouded in a dusty cocoon--likely the result of past eruptive activity--leaving its true nature enigmatic. We present the most detailed X-ray study of Wd1-9 to date, using X-rays that pierce through its cocoon with the aim to uncover its nature and evolutionary state. We utilize 36 Chandra observations of Wd1 from the 'Extended Westerlund 1 and 2 Open Clusters Survey' (EWOCS), plus eight archival datasets, totalling 1.1 Ms. This dataset allows investigation of long-term variability and periodicity in Wd1-9, while X-ray colours and spectra are analysed over time to uncover patterns that shed light on its nature. Wd1-9 exhibits significant long-term X-ray variability, within which we identify a strong 14-day periodic signal. We interpret this as the orbital period, marking the first period determination for the system. The X-ray spectrum of Wd1-9 is thermal and hard (kT approximately 3.0 keV), resembling the spectra of bright Wolf-Rayet (WR) binaries in Wd1, while a strong Fe emission line at 6.7 keV indicates hot plasma from a colliding-wind X-ray binary. Wd1-9, with evidence of past mass loss, circumbinary material, a hard X-ray spectrum, and a newly detected 14-day period, displays all the hallmarks of a binary--likely a WR+OB--that recently underwent early Case B mass transfer. Its sgB[e] classification is likely phenomenological reflecting emission from the dense circumbinary material. This places Wd1-9 in a rarely observed phase, possibly revealing a newly formed WN star, bridging the gap between immediate precursors and later evolutionary stages in Wd1.

We investigate the influence of supernova (SN) feedback on the satellites of elliptical host galaxies using hydrodynamic simulations. Utilizing a modified version of the GADGET-3 code, we perform cosmological zoom-in simulations of 11 elliptical galaxies with stellar masses in the range $10^{11} M_{\odot} < M_{*} < 2 \times 10^{11} M_{\odot}$. We conduct two sets of simulations with identical initial conditions: the Fiducial model, which includes a three-phase SN mechanical wind, and the weak SN feedback model, where nearly all SN energy is released as thermal energy with a reduced SN wind velocity. Our comparison shows minimal differences in the elliptical host galaxies, but significant variations in the physical properties of satellite galaxies. The weak SN feedback model produces a larger number of satellite galaxies compared to the Fiducial model, and significantly more than observed. For satellite galaxies with stellar masses above $10^{8}$ $M_{\odot}$, the weak SN feedback model generates approximately five times more satellites than observed in the xSAGA survey. Most of these overproduced satellites have small stellar masses, below $10^{10}$ $M_{\odot}$. Additionally, satellites in the weak SN feedback model are about 3.5 times more compact than those observed in the SAGA survey and the Fiducial model, with metallicities nearly 1 dex higher than observed values. In conclusion, the satellite galaxies in the Fiducial model, which includes mechanical SN feedback, exhibit properties more closely aligned with observations. This underscores the necessity of incorporating both mechanical AGN and SN feedback to reproduce the observed properties of elliptical galaxy and their satellites in simulations.

We present and discuss optical emission line properties obtained from the analysis of Sloan Digital Sky Survey (SDSS) spectra for an X-ray selected sample of 3684 galaxies (0.002 < z < 0.55), drawn from the eRASS1 catalog. We modeled SDSS-V DR19 spectra using the NBursts full spectrum fitting technique with E-MILES simple stellar populations (SSP) models and emission line templates to decompose broad and narrow emission line components for correlation with X-ray properties. We place the galaxies on the Baldwin-Phillips-Terlevich (BPT) diagram to diagnose their dominant excitation mechanism. We show that the consistent use of the narrow component fluxes shifts most galaxies systematically and significantly upward to the active galactic nuclei (AGN) region on the BPT diagram. On this basis, we confirm the dependence between a galaxys position on the BPT diagram and its (0.2-2.3 keV) X-ray/H$α$ flux ratio. We also verified the correlation between X-ray luminosity and emission line luminosities of the narrow [O\iii]$λ5007$ and broad H$α$ component; as well as the relations between the Supermassive Black Hole (SMBH) mass, the X-ray luminosity, and the velocity dispersion of the stellar component ($σ_{*}$) on the base on the unique sample of optical spectroscopic follow-up of X-ray sources detected by eROSITA. These results highlight the importance of emission line decomposition in AGN classification and refine the connection between X-ray emission and optical emission line properties in galaxies.

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 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 (SHELLQs) survey with NIRCam and NIRSpec observations. We find that the observed location of these quasars in the SMBH-galaxy mass plane (log MBH ~ 8-9; log M* ~9.5-11) is consistent with a non-evolving intrinsic mass relation with dispersion (0.80_{-0.28}^{+0.23} dex) higher than the local value (~0.3-0.4 dex). Our analysis is based on a forward model of systematics and includes a consideration of the impact of selection effects and measurement uncertainties, an assumption on the slope of the mass relation, and finds 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 MBH would require an unrealistically low intrinsic dispersion (~0.22 dex) and a lower AGN fraction (~0.6%). Consequently, our results predict a large population of AGNs at lower black hole masses, as are now just starting to be discovered in focused efforts with JWST.

We have carried out a systematic search for galaxy-scale lenses exploiting multiband imaging data from the third public data release of the Hyper Suprime-Cam (HSC) survey with the focus on false-positive removal, after applying deep learning classifiers to all ~110 million sources with an i-Kron radius above 0."8 .<!--inline-formula id="FI1"><alternatives><tex-math id="tex_eq1"><![CDATA[$\[0^{\prime\prime}_\cdot8\]$]]></tex-math><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline" id="mml_eq1"><mml:msubsup><mml:mn>0</mml:mn><mml:mo>ṡ</mml:mo><mml:mrow class="MJX-TeXAtom-ORD"><mml:mi class="MJX-variant" mathvariant="normal">'</mml:mi><mml:mi class="MJX-variant" mathvariant="normal">'</mml:mi></mml:mrow></mml:msubsup><mml:mn>8</mml:mn></mml:math><inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" id="img_eq1" mime-subtype="png" mimetype="image" xlink:href="aa54425-25-eq1.png"/></alternatives></inline-formula--> To improve the performance, we tested the combination of multiple networks from our previous lens search projects and found the best performance by averaging the scores from five of our networks. Although this ensemble network leads already to a false-positive rate of ~0.01% at a true-positive rate (TPR) of 75% on known real lenses, we have elaborated techniques to further clean the network candidate list before visual inspection. In detail, we tested the rejection using SExtractor and the modeling network from HOLISMOKES IX, which resulted together in a candidate rejection of 29% without lowering the TPR. After the initial visual inspection stage to remove obvious non-lenses, 3408 lens candidates of the ~110 million parent sample remained. We carried out a comprehensive multistage visual inspection involving eight individuals and identified finally 95 grade A (average grade G ≥ 2.5) and 503 grade B (2.5> G ≥ 1.5) lens candidates, including 92 discoveries showing clear lensing features that are reported for the first time. This inspection also incorporated a novel environmental characterization using histograms of photometric redshifts. We publicly release the average grades, mass model predictions, and environment characterization of all visually inspected candidates, while including references for previously discovered systems, which makes this catalog one of the largest compilation of known lenses. The results demonstrate that (1) the combination of multiple networks enhances the selection performance and (2) both automated masking tools as well as modeling networks, which can be easily applied to hundreds of thousands of network candidates expected in the near future of wide-field imaging surveys, help reduce the number of false positives, which has been the main limitation in lens searches to date.

A crucial ingredient affecting fast neutrino flavor conversion in core-collapse supernovae (SNe) is the shape of the angular distribution of the electron-neutrino lepton number (ELN). The presence of an ELN crossing signals favorable conditions for flavor conversion. However, the dependence of ELN crossings on the SN properties is only partially understood. We investigate a suite of 12 spherically symmetric neutrino-hydrodynamics simulations of the core collapse of a SN with a mass of $18.6 M_\odot$; each model employs different microphysics (i.e., three different nuclear equations of state, with and without muon creation) and includes or not a mixing-length treatment for proto-neutron star convection. We solve the Boltzmann equations to compute the neutrino angular distributions relying on static fluid properties extracted from each of the SN simulations in our suite for six selected post-bounce times. We explore the dependence of the ELN distributions on the SN microphysics and proto-neutron star convection. We find that the latter shifts the proto-neutron star radius outwards, favoring the appearance of ELN crossings at larger radii. On the other hand, muon creation causes proto-neutron star contraction, facilitating the occurrence of ELN crossings at smaller radii. These effects mildly depend on the nuclear equation of state. Our findings highlight the subtle impact of the SN microphysics, proto-neutron star convection, and neutrino transport on the ELN angular distributions.