Muon conversion is one of the best probes of charged lepton flavor violation. The experimental limit is soon expected to improve by four orders of magnitude, thus calling for precise predictions of the shape of the signal spectrum. Equally important are precise predictions for muon decay-in-orbit, the main background for muon conversion. While the calculation of electromagnetic corrections to the two processes above the nuclear scale does not involve significant challenges, it becomes substantially more complex below that scale due to multiple scales, bound-state effects and experimental setup. Here, we present a systematic framework that addresses these challenges by resorting to a series of effective field theories. Combining Heavy Quark Effective Theory (HQET), Non-Relativistic QED (NRQED), potential NRQED, Soft-Collinear Effective Theory I and II, and boosted HQET, we derive a factorization theorem and present the renormalization group equations. Our framework allows for the proper calculation of precise predictions for the rates of the two processes, with crucial implications for the upcoming muon conversion searches. We also provide the most accurate prediction of the signal shape for those searches.

Unveiling the physical structure of protoplanetary disks is crucial for interpreting the diversity of the exoplanet population. Until recently, the census of the physical properties of protoplanetary disks probed by mid-infrared observations was limited to the solar neighborhood (d ≲ 250 pc). However, nearby star-forming regions (SFRs) such as Taurus—where no O-type stars reside—are not representative of the environments where the majority of the planet formation occurs in the Galaxy. The James Webb Space Telescope (JWST) now enables observations of disks in distant high-mass SFRs, where strong external far-ultraviolet radiation is expected to impact those disks. Nevertheless, a detailed characterization of the population of externally irradiated disks is still lacking. We use the thermochemical code ProDiMo to model JWST/MIRI spectroscopy and archival visual/near-infrared photometry aiming to constrain the physical structure of the irradiated disk around the solar-mass star XUE 1 in NGC 6357 (d ≈ 1690 pc). Our findings are as follows. (1) Mid-infrared dust emission features are explained by amorphous and crystalline silicates with compositions similar to nearby disks. (2) The molecular features detected with MIRI originate within the first ∼1 au, consistent with results from slab models. (3) Our model favors a disk truncated at 10 au with a gas-to-dust ratio of unity in the outskirts. (4) Comparing models of the same disk structure under different irradiation levels, we find that strong external irradiation raises gas temperature tenfold and boosts water abundance beyond 10 au by a factor of 100.

We renormalize the soft function entering the factorization and resummation of the qg parton-scattering channel of the Drell-Yan process near the kinematic threshold <inline-formula><mml:math><mml:mover><mml:mi>s</mml:mi><mml:mo>̂</mml:mo></mml:mover></mml:math></inline-formula> → Q² at next-to-leading power in the expansion around z ≡ Q²/<inline-formula><mml:math><mml:mover><mml:mi>s</mml:mi><mml:mo>̂</mml:mo></mml:mover></mml:math></inline-formula> = 1, and solve its renormalization-group equation.

We here measure, for the first time, adjoint chromoelectric correlators at finite temperatures that encode the diffusion of quarkonium in the medium. Understanding the dynamics of quarkonium in the QGP plays an essential role in understanding quarkonium suppression and the QGP in general. We perform SU(3) gauge theory calculations and use gradient flow to improve the signal-to-noise ratio and chromoelectric field discretizations. The continuum limit and the zero-flow-time extrapolation are performed, and the final result is compared with perturbative results. We observe that the correlators at a high temperature are well described by the perturbative form; furthermore, we observe multiplicative scaling of the adjoint correlators with respect to the fundamental correlator describing heavy quark diffusion.

Collective oscillations in dense neutrino gases (flavor waves) are notable for their instabilities that cause fast flavor conversion. We develop a quantum theory of interacting neutrinos and flavor wave quanta, which are analogous to plasmons but also carry flavor. The emission or absorption of such flavor plasmons <inline-formula><mml:math><mml:mi>ψ</mml:mi></mml:math></inline-formula>, or "flavomons," changes the neutrino flavor. When an angular crossing occurs, the process <inline-formula><mml:math><mml:mrow><mml:msub><mml:mrow><mml:mi>ν</mml:mi></mml:mrow><mml:mrow><mml:mi>μ</mml:mi></mml:mrow></mml:msub><mml:mo>→</mml:mo><mml:msub><mml:mrow><mml:mi>ν</mml:mi></mml:mrow><mml:mrow><mml:mi>e</mml:mi></mml:mrow></mml:msub><mml:mo>+</mml:mo><mml:mi>ψ</mml:mi></mml:mrow></mml:math></inline-formula> is more rapid than its inverse along the direction of the crossing, triggering stimulated <inline-formula><mml:math><mml:mi>ψ</mml:mi></mml:math></inline-formula> emission and fast instability. Calculating the rate via Feynman diagrams matches the fast instability growth rate. Our novel <inline-formula><mml:math><mml:mi>ν</mml:mi></mml:math></inline-formula> and <inline-formula><mml:math><mml:mi>ψ</mml:mi></mml:math></inline-formula> kinetic equations, corresponding to quasilinear theory, describe instability evolution without resolving the small scales of the flavomon wavelength, potentially overcoming the main challenge of fast flavor evolution.

Ongoing and upcoming wide-field surveys at different wavelengths will measure the distribution of galaxy clusters with unprecedented precision, demanding accurate models for the two-point correlation function (2PCF) covariance. In this work we assessed a semi-analytical framework for the cluster 2PCF covariance that employs three nuisance parameters to account for non-Poissonian shot noise, residual uncertainties in the halo bias model, and sub-leading noise terms. We calibrated these parameters on a suite of fast approximate simulations generated by PINOCCHIO as well as full N-body simulations from OpenGADGET3. We demonstrate that PINOCCHIO can reproduce the 2PCF covariance measured in OpenGADGET3 at the few percent level, provided the mass functions are carefully rescaled. Resolution tests confirm that high particle counts are necessary to capture shot-noise corrections, especially at high redshifts. We performed the parameter calibration across multiple cosmological models, showing that one of the nuisance parameters, the non-Poissonian shot-noise correction (α), depends mildly on the amplitude of matter fluctuations (σ₈). In contrast, the remaining two parameters, β, which controls the bias correction, and γ, which controls the secondary shot-noise correction, exhibit more significant variation with redshift and halo mass. Overall, our results underscore the importance of calibrating covariance models on realistic mock catalogs that replicate the selection function of forthcoming surveys and highlight that approximate methods, when properly tuned, can effectively complement full N-body simulations for precision cluster cosmology.

Context. AGN feedback is a crucial ingredient for understanding galaxy evolution. However, a complete quantitative time-dependent framework, including the dependence of such feedback on AGN, host galaxy, and host halo properties, is yet to be developed. Aims. Using the complete sample of 682 radio AGN from the LOFAR-eFEDS survey (z < 0.4), we derive the average jet power of massive galaxies and its variation as a function of stellar mass (M_*), halo mass (M_h) and radio morphology. Methods. We compare the incidence distributions of compact and complex radio AGN as a function of specific black hole kinetic power, λ_Jet, and synthesise, for the first time, the radio luminosity function (RLF) by M_* and radio morphology. Our RLF and derived total radio AGN kinetic luminosity density, log Ω_kin/[W Mpc^‑3] = 32.15_‑0.34^+0.18, align with previous work. Results. Kinetic feedback from radio AGN dominates over any plausible inventory of radiatively driven feedback for galaxies with log M_*/M_⊙ > 10.6. More specifically, it is the compact radio AGN that dominate this global kinetic energy budget for all but the most massive galaxies (10.6 < log M_*/M_⊙ < 11.5). Subsequently, we compare the average injected jet energy (E̅_Jet) against the galaxy and halo binding energy (U_bin), and against the total thermal energy of the host gas (E_th) within halos. We find that compact radio AGN lack the energy to fully unbind galaxies, but complex AGN reach E̅_Jet > U_bin in the most massive systems (log M_*/M_⊙ > 11.5), where such energy is likely deposited beyond the typical galaxy sizes. On halo scales, neither compact nor complex radio AGN provide enough energy to fully disrupt the global gas distribution, especially not for the most massive clusters. On the other hand, E̅_Jet greatly surpasses the global E_th for groups, thereby providing a crucial input to the gas and thermodynamical balance in these systems. Finally, we show that AGN jets can also significantly impact the local thermodynamical balance in the cores of large groups and massive clusters. Overall, our findings provide important insights into jet powering, accretion processes and black hole-galaxy coevolution via AGN feedback.

Future ground- and space-based telescopes will enable the characterization of rocky exoplanets in reflected light, allowing for the observation of their albedo, which depends on surface, cloud, and atmospheric properties. Identifying key atmospheric, cloud, and surface features is essential for assessing the potential habitability of these exoplanets. We present reference spectra and phase curves for a spatially unresolved Earth-like exoplanet in reflected and polarized light, highlighting how wavelength-dependent and phase-angle-dependent reflectance reveals key planetary properties. Performing simulations with the 3D Monte Carlo radiative transfer code MYSTIC, we improve surface and cloud modeling by introducing validated wavelength-dependent albedo maps of Earth's seasonal and spectral features, as well as a novel treatment of subgrid cloud variability and inhomogeneities based on reanalysis data from ERA5. Our models incorporate high-resolution 3D cloud structures, demonstrating that subgrid cloud variability significantly affects both intensity and polarization. It reduces total reflectance and increases phase curve variability, especially at large phase angles where ocean glint dominates. Additionally, we show that neglecting realistic wavelength-dependent albedo maps leads to a significant overestimation of the vegetation red edge feature in reflected light spectra. Comparing an ocean planet to an Earth-like planet with seasonal cloud variability, we find that polarization is far more sensitive than intensity alone to identify the two scenarios. Moreover, polarization captures richer information on surface properties, making it a critical tool for breaking degeneracies in retrieval frameworks. We present detailed model simulations that provide a ground-truth reference for observing Earth as an exoplanet and that serve as critical benchmarks for developing observational strategies and retrieval frameworks for future telescopes targeting small rocky exoplanets. Furthermore, this study informs model requirements and establishes a framework to optimize strategies for characterizing rocky exoplanets, emphasizing the pivotal role of polarization in breaking retrieval degeneracies across different models.

We describe a family of twisted partition functions for the relativistic spinning particle models. For suitable choices of fugacities this computes a refined Euler characteristics that counts the dimension of the physical states for arbitrary picture and, furthermore, encodes the complete BV-spectrum of the effective space-time gauge theory originating from this model upon second quantization. The relation between twisted world-line partition functions and the spectrum of the space-time theory is most easily seen on-shell but we will give an off-shell description as well. Finally we discuss the construction of a space-time action in terms of the world-line fields in analogy to string field theory.

An accretion-induced collapse (AIC) or merger-induced collapse (MIC) of white dwarfs (WDs) in binary systems is an interesting path to neutron star (NS) and magnetar formation, alternative to stellar core-collapse and NS mergers. Such events could add a population of compact remnants in globular clusters; they are expected to produce yet unidentified electromagnetic transients including gamma-ray and radio bursts, and to act as sources of transiron elements, neutrinos, and gravitational waves. Here, we present the first long-term (≳5 s postbounce) hydrodynamical simulations in axisymmetry (2D), using an energy- and velocity-dependent three-flavor neutrino transport based on a two-moment scheme. Our set of six models includes initial WD configurations for different masses, central densities, rotation rates, and angular momentum profiles. Our simulations demonstrate that rotation plays a crucial role for the protoneutron star (PNS) evolution and ejecta properties. We find early neutron-rich ejecta and an increasingly proton-rich neutrino-driven wind at later times in a nonrotating model, in agreement with electron-capture supernova models. In contrast to that and different from previous results, our rotating models eject proton-rich material initially and increasingly more neutron-rich matter as time advances, because an extended accretion torus forms around the PNS and feeds neutrino-driven bipolar outflows for many seconds. AIC and MIC events are thus potential sites of r-process element production, which may imply constraints on their occurrence rates. Finally, our simulations neglect the effects of triaxial deformation and magnetic fields, yet they provide valuable reference cases for comparison with future long-term magnetohydrodynamic and 3D AIC studies.

Context. Through gravitational lensing, galaxy clusters can magnify supernovae (SNe) and thereby create multiple images of the same SN. This enables measurements of cosmological parameters (primarily the Hubble constant), which will be increasingly important in the context of upcoming surveys from the Nancy Grace Roman Space Telescope (Roman) and Vera C. Rubin Observatory. Aims. We study the prospects of detecting strongly lensed supernovae in cluster fiels with Roman's High Latitude Time Domain Survey (HLTDS) and the Vera C. Rubin Observatory's Legacy Survey of Space and Time (LSST). Methods. We employed two approaches: one focusing on known multiply imaged galaxies (arcs) behind cluster fields, along with the SN rates specific to those galaxies (arc-specific), while the second is based on the expected number of lensed SNe exploding in a given volume behind a galaxy cluster (volumetric). We collected all the clusters in the literature that feature a) a well-constrained lens model and b) multiply imaged galaxies behind clusters with high-quality data for the multiply imaged galaxies behind clusters. This allowed us to determine the supernova rate for each galaxy. We provide predictions for 46 clusters visible to the Vera C. Rubin Observatory, as well as for 9 observable by Roman's HLTDS, depending on whether the clusters fall within the survey's observing field. Results. We predict that the number of multiply imaged SNe discovered by LSST in its first three years is 3.95 ± 0.89 from the first approach or 4.94 ± 1.02 from the second. Based on the current proposed observing strategy for the HLTDS, which specifies the requirements on galactic and ecliptic latitudes, the expected number of multiply imaged supernovae ranges from 0.38 ± 0.15 to 5.2 ± 2.2, depending on the specific cluster observed. However, the exact fields to be targeted remain a matter of discussion. Conclusions. We conclude that LSST offers great prospects for detecting multiply imaged SNe. If adequate follow-up campaigns are conducted, these capabilities will enable measurements of cosmological parameters independent of conventional probes. These predictions are effectively lower limits, as we only considered the most massive and well-studied clusters in the present work. Here, we provide a recommendation for HLTDS observing field selection, namely: either MACS J0553.4-3342 or Abell 1758a should be observed by the survey to maximize the number of potential multiply imaged SN discoveries.

Aims. The Spectrum Roentgen Gamma (SRG) eROSITA all-sky survey marks the beginning of the data-rich era by conducting population studies of tidal disruption events (TDEs) and other rare X-ray transients. This paper presents a systematic study of X-ray-selected canonical TDEs discovered in the western Galactic hemisphere of the first two eROSITA all-sky surveys (eRASS1 and eRASS2) performed between Dec 2019 and Dec 2020. Methods. We compiled a TDE sample from the catalog of eROSITA's extragalactic transients and variables eRO-ExTra, which includes X-ray sources with a variability significance and fractional amplitude over four between eRASS1 and eRASS2, not associated with known active galactic nuclei (AGNs). Each X-ray source is associated with an optical counterpart from the Legacy Survey DR10 (LS10). Canonical TDEs were selected based on their X-ray light-curve properties (single flare or decline), soft X-ray spectra (Γ>3), and the absence of archival X-ray variability and AGN signatures in their host photometry and spectroscopy. Results. We present 31 X-ray-selected TDE candidates associated with optical counterparts with redshifts of 0.02<z<0.34 and luminosities of 5.7×10⁴¹<L_X<5.3×10⁴⁴ ergs^‑1 in the 0.2‑6.0 keV rest frame. The sample contains 30 canonical TDEs and one off-nuclear TDE candidate. The X-ray luminosity function derived from this sample is best fit by a double power law with a luminosity break at 10⁴⁴ ergs^‑1, corresponding to the Eddington-limiting prediction. The result is in agreement with previous observational and theoretical estimates. This corresponds to a TDE volumetric rate of (2.3_‑0.9^+1.2) × 10^‑7 Mpc^‑3 yr^‑1 (≈1.2×10^‑5 events per galaxy per year). The TDE host galaxies show a green-valley overdensity, as was previously found in X-ray and optical studies. In addition, 20%, 30%, and 15% of our X-ray-selected sample exhibit flares in the optical, mid-infrared (mid-IR), or radio bands, respectively. We discuss the differences between X-ray, optical, and mid-IR TDE populations and the origins of multiwavelength flares in the context of the obscuring envelope and stream-stream collision models. Finally, we highlight TDE subpopulations that are not included in the canonical sample and should be explored in the future.

Context. Traditionally, weak lensing cosmological surveys have been analyzed using summary statistics that were either motivated by their analytically tractable likelihoods (e.g., power spectrum) or by their ability to access some higher-order information (e.g., peak counts), but at the cost of requiring a simulation-based inference approach. In both cases, even if the statistics can be very informative, they are not designed nor guaranteed to be statistically sufficient (i.e., to capture all the cosmological information content of the data). With the rise of deep learning, however, it has becomes possible to create summary statistics that are specifically optimized to extract the full cosmological information content of the data. Yet, a fairly wide range of loss functions have been used in practice in the weak lensing literature to train such neural networks, leading to the natural question of whether a given loss should be preferred and whether sufficient statistics can be achieved in theory and in practice under these different choices. Aims. We compare different neural summarization strategies that have been proposed in the literature to identify the loss function that leads to theoretically optimal summary statistics for performing full-field cosmological inference. In doing so, we aim to provide guidelines and insights to the community to help guide future neural network-based cosmological inference analyses. Methods. We designed an experimental setup that allows us to isolate the specific impact of the loss function used to train neural summary statistics on weak lensing data at fixed neural architecture and simulation-based inference pipeline. To achieve this, we developed the sbi_lens JAX package, which implements an automatically differentiable lognormal weak lensing simulator and the tools needed to perform explicit full-field inference with a Hamiltonian Monte Carlo (HMC) sampler over this model. Using sbi_lens, we simulated a wCDM LSST Year 10 weak lensing analysis scenario in which the full-field posterior obtained by HMC sampling gives us a ground truth that can be compared to different neural summarization strategies. Results. We provide theoretical insight into the different loss functions being used in the literature, including mean squared error (MSE) regression, and show that some do not necessarily lead to sufficient statistics, while those motivated by information theory, in particular variational mutual information maximization (VMIM), can in principle lead to sufficient statistics. Our numerical experiments confirm these insights, and we show on our simulated wCDM scenario that the figure of merit (FoM) of an analysis using neural summary statistics optimized under VMIM achieves 100% of the reference Ω_c‑σ₈ full-field FoM, while an analysis using summary statistics trained under simple MSE achieves only 81% of the same reference FoM.

The upcoming galactic core-collapse supernova is expected to produce a considerable number of neutrino events within terrestrial detectors. By using Bayesian inference techniques, we address the feasibility of distinguishing among various neutrino flavor conversion scenarios in the supernova environment, using such a neutrino signal. In addition to the conventional Mikheev-Smirnov-Wolfenstein, we explore several more sophisticated flavor conversion scenarios, such as spectral swapping, fast flavor conversions, flavor equipartition caused by nonstandard neutrino interactions, magnetically induced flavor equilibration, and flavor equilibrium resulting from slow flavor conversions. Our analysis demonstrates that with a sufficiently large number of neutrino events during the supernova accretion phase (exceeding several hundreds), there exists a good probability of distinguishing among feasible neutrino flavor conversion scenarios in the supernova environment.

Novel interactions beyond the four known fundamental forces in nature (electromagnetic, gravitational, strong, and weak interactions) may arise due to "new physics" beyond the standard model, manifesting as a "fifth force." This review focuses on spin-dependent fifth forces mediated by exotic bosons such as spin-0 axions and axionlike particles and spin-1 <inline-formula><mml:math><mml:mrow><mml:msup><mml:mrow><mml:mi>Z</mml:mi></mml:mrow><mml:mrow><mml:mo>'</mml:mo></mml:mrow></mml:msup></mml:mrow></mml:math></inline-formula> bosons, dark photons, and paraphotons. Many of these exotic bosons are candidates to explain the nature of dark matter and dark energy, and their interactions may violate fundamental symmetries. Spin-dependent interactions between fermions mediated by the exchange of exotic bosons have been investigated in a variety of experiments, particularly at the low-energy frontier. Experimental methods and tools used to search for exotic spin-dependent interactions, such as atomic comagnetometers, torsion balances, nitrogen-vacancy spin sensors, and precision atomic and molecular spectroscopy, are described. A complete set of interaction potentials, derived based on quantum field theory with minimal assumptions and characterized in terms of reduced coupling constants, are presented. A summary of existing experimental and observational constraints on exotic spin-dependent interactions is given, in the process illustrating the current research landscape and promising directions of further research.

We compute the partition function for the $N=1$ spinning particle, including pictures and the large Hilbert space, and show that it counts the dimension of the BRST cohomology in two- and four-dimensional target space. We also construct a quadratic action in the target space. Furthermore, we find a consistent interaction as a derived bracket based on the associative product of world line fields, leading to an interacting theory of multiforms in space-time. Finally, we comment on the equivalence of the multiform theory with a Dirac fermion. We also identify the chiral anomaly of the latter with a Hodge anomaly for the multiform theory, which manifests itself as a deformation of the gauge fixing.

So far, even the highest resolution galaxy formation simulations with gravitational softening have failed to reproduce realistic life cycles of star clusters. We present the first star-by-star galaxy models of star cluster formation to account for hydrodynamics, star formation, stellar evolution, and collisional gravitational interactions between stars and compact remnants using the updated SPHGAL + KETJU code, part of the GRIFFIN project. Gravitational dynamics in the vicinity of <inline-formula><tex-math id="TM0001" notation="LaTeX">$>3$</tex-math></inline-formula> M<inline-formula><tex-math id="TM0002" notation="LaTeX">$_\odot$</tex-math></inline-formula> stars and their remnants are solved with a regularized integrator (KETJU) without gravitational softening. Comparisons of idealized star cluster evolution with SPHGAL + KETJU and direct N-body show broad agreement and the failure of simulations that use gravitational softening. In the hydrodynamical simulations of idealized dwarf galaxies run with SPHGAL + KETJU, clusters up to <inline-formula><tex-math id="TM0003" notation="LaTeX">$\sim 900$</tex-math></inline-formula> M<inline-formula><tex-math id="TM0004" notation="LaTeX">$_\odot$</tex-math></inline-formula> form compact (effective radii 0.1-1 pc) and their sizes increase by up to a factor of 10 in agreement with previous N-body simulations and the observed sizes of exposed star clusters. The sizes increase rapidly once the clusters become exposed due to photoionizing radiation. On average 63 per cent of the gravitationally bound clusters disrupt during the first 100 Myr of evolution in the galactic tidal field. The addition of collisional dynamics reduces the fraction of supernovae in bound clusters by a factor of <inline-formula><tex-math id="TM0005" notation="LaTeX">$\sim 1.7$</tex-math></inline-formula>; however, the global star formation and outflow histories change by less than 30 per cent. We demonstrate that the accurate treatment of gravitational encounters with massive stars enables more realistic star cluster life cycles from the earliest stages of cluster formation until disruption in simulated low-mass galaxies.

Galaxy and halo scaling relations, connecting a broad range of parameters, are well established from observations. The origin of many of these relations and their scatter is still a matter of debate. It remains a sizable challenge for models to simultaneously and self-consistently reproduce as many scaling relations as possible. We introduce the Magneticum Pathfinder hydrodynamical cosmological simulation suite, to date the suite that self-consistently covers the largest range in box volumes and resolutions. It is the only cosmological simulation suite that is tuned on the hot gas content of galaxy clusters instead of the stellar mass function. By assessing the successes and shortcomings of tuning to the hot gas component of galaxy clusters, we aim to further our understanding of the physical processes shaping the Universe. We analyze the importance of the hot and cold gas components for galaxy and structure evolution. We analyze 28 scaling relations, covering large-scale global parameters as well as internal properties for halos ranging from massive galaxy clusters down to galaxies, and show their predicted evolution from z=4 to z=0 in comparison with observations. These include the halo-to-stellar-mass and Kennicutt--Schmidt relations, the cosmic star formation rate density as well as the Fundamental Plane. Magneticum Pathfinder matches a remarkable number of the observed scaling relations from z=4 to z=0, including challenging relations like the number density of quiescent galaxies at cosmic dawn, the mass--size evolution, the mass--metallicity relation, the Magorrian relation, and the temperature--mass relation. We compile our data to allow for straightforward future comparisons. Galaxy properties and scaling relations arise naturally and the large scatter in observables at high redshift is crucial to distinguish the various galaxy formation models reproducing the z=0 relations.

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.

Future telescopes will characterize rocky exoplanets in reflected light, revealing their albedo, which depends on surface, cloud, and atmospheric properties. Identifying these features is crucial for assessing habitability. We present reference spectra and phase curves for an unresolved Earth-like exoplanet in reflected and polarized light, showing how phase- and wavelength-dependent reflectance reveals key planetary properties. Using the 3D radiative transfer code MYSTIC, we enhance surface and cloud modeling with validated, wavelength-dependent albedo maps of Earth's seasonal and spectral features, alongside a novel treatment of sub-grid cloud variability using ERA5 reanalysis data. Our models, incorporating high-resolution 3D cloud structures, show that sub-grid cloud variability reduces total reflectance and increases phase curve variability, especially at large phase angles where ocean glint dominates. We also find that neglecting wavelength-dependent albedo maps overestimates the vegetation red edge in spectra. Comparing an Ocean planet to an Earth-like planet with seasonal cloud variability, we show that polarization is more sensitive than intensity alone in distinguishing both cases. Moreover, polarization captures richer surface details, making it a crucial tool for resolving retrieval degeneracies. Our simulations serve as a reference for observing Earth as an exoplanet and provide benchmarks for optimizing observational strategies and retrieval frameworks for future telescopes targeting small, rocky exoplanets.

We show experimentally that an effect of motion of ions, observed in a plasma-based accelerator, depends inversely on the plasma ion mass. The effect appears within a single wakefield event and manifests itself as a bunch tail, occurring only when sufficient motion of ions suppresses wakefields. Wakefields are driven resonantly by multiple bunches, and simulation results indicate that the ponderomotive force causes the motion of ions. In this case, the effect is also expected to depend on the amplitude of the wakefields, experimentally confirmed through variations in the drive bunch charge.

Context. The supernova remnant (SNR) Cassiopeia A (Cas A) offers a unique opportunity to study supernova (SN) explosion dynamics and remnant interactions with the circumstellar medium (CSM). Recent observations with the James Webb Space Telescope have unveiled an enigmatic structure within the remnant, termed "Green Monster" (GM), whose properties indicate a CSM origin. Aims. Our goal is to investigate the properties of the GM and uncover the origin of its intriguing pockmarked structure, characterized by nearly circular holes and rings. We aim to examine the role of small-scale ejecta structures in shaping these features through their interaction with a dense circumstellar shell. Methods. We adopted a neutrino-driven SN model to trace the evolution of its explosion from core collapse to the age of the Cas A remnant using high-resolution 3D magnetohydrodynamic simulations. Besides other processes, the simulations include self-consistent calculations of radiative losses, accounting for deviations from electron-proton temperature equilibration and ionization equilibrium, as well as the ejecta composition derived from the SN. Results. The observed GM morphology can be reproduced by the interaction of dense ejecta clumps and fingers with an asymmetric, forward-shocked circumstellar shell. The clumps and fingers form by hydrodynamic instabilities growing at the interface between SN ejecta and shocked CSM. Radiative cooling accounting for effects of non-equilibrium of ionization enhances the ejecta fragmentation, forming dense knots and thin filamentary structures that penetrate the shell, producing a network of holes and rings with properties similar to those observed. Conclusions. The origin of the holes and rings in the GM can be attributed to the interaction of ejecta with a shocked circumstellar shell. By constraining the timing of this interaction and analyzing the properties of these structures, we provide a distinction of this scenario from an alternative hypothesis, which attributes these features to fast-moving ejecta knots penetrating the shell ahead of the forward shock.

Context. Recent observations with the James Webb Space Telescope (JWST) have revealed unprecedented details of an intricate filamentary structure of unshocked ejecta within the young supernova remnant (SNR) Cassiopeia A (Cas A), offering new insights into the mechanisms governing supernova (SN) explosions and the subsequent evolution of ejecta. Aims. We aim to investigate the origin and evolution of the newly discovered web-like network of ejecta filaments in Cas A. Our specific objectives are: (i) to characterize the three-dimensional (3D) structure and kinematics of the filamentary network and (ii) to identify the physical mechanisms responsible for its formation. Methods. We performed high-resolution, 3D hydrodynamic (HD) and magneto-hydrodynamic (MHD) simulations to model the evolution of a neutrino-driven SN from the explosion to its remnant with the age of 1000 years. The initial conditions, set shortly after the shock breakout at the stellar surface, are based on a 3D neutrino-driven SN model that closely matches the basic properties of Cas A. Results. We found that the magnetic field has little impact on the evolution of unshocked ejecta, so we focused most of the analysis on the HD simulations. A web-like network of ejecta filaments, with structures compatible with those observed by JWST (down to scales ≈0.01 pc), naturally forms during the SN explosion. The filaments result from the combined effects of processes occurring soon after the core collapse, including the expansion of neutrino-heated bubbles formed within the first second after the explosion, hydrodynamic instabilities triggered during the blast propagation through the stellar interior, and the Ni-bubble effect following the shock breakout. The interaction of the reverse shock with the ejecta progressively disrupts the filaments through the growth of hydrodynamic instabilities. By around 700 years, the filamentary network becomes unobservable. Conclusions. According to our models, the filaments observed by JWST in Cas A most likely preserve a "memory" of the early explosion conditions, reflecting the processes active during and immediately after the SN event. Notably, a filamentary network closely resembling that observed in Cas A is naturally produced by a neutrino-driven SN explosion.

AT 2019aalc is a peculiar sequence of highly variable emission events observed towards the nucleus of the broad-line 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 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 Bowen fluorescence and the coronal lines vary (roughly) in tandem with these "bumps" in the broad-band light-curve. Most of the observed behavior of AT 2019aalc links it to the growing class of Bowen fluorescence flares (BFFs) 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 (pre-existing) AGN accretion disk.

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 axion-like 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 KKLT framework, featuring a single volume modulus and $C_4$ 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.

Frequentist parameter inference using profile likelihoods has received increased attention in the cosmology literature recently since it can give important complementary information to Bayesian credible intervals. Here, we give a pedagogical review of frequentist parameter inference in cosmology and focus on when the graphical profile likelihood construction gives meaningful constraints, i.e. confidence intervals with correct coverage. This construction rests on the assumption of the asymptotic limit of a large data set such as in Wilks' theorem. We assess the validity of this assumption in the context of three cosmological models with Planck 2018 Plik_lite data. While our tests for the <inline-formula><mml:math><mml:mi>Λ</mml:mi><mml:mi>CDM</mml:mi></mml:math></inline-formula> model indicate that the profile likelihood method gives correct coverage, <inline-formula><mml:math><mml:mi>Λ</mml:mi><mml:mi>CDM</mml:mi></mml:math></inline-formula> with the sum of neutrino masses as a free parameter appears consistent with a Gaussian near a boundary motivating the use of the boundary-corrected or Feldman-Cousins graphical method; for <inline-formula><mml:math><mml:msub><mml:mi>w</mml:mi><mml:mn>0</mml:mn></mml:msub><mml:mi>CDM</mml:mi></mml:math></inline-formula> with the equation of state of dark energy, <inline-formula><mml:math><mml:msub><mml:mi>w</mml:mi><mml:mn>0</mml:mn></mml:msub></mml:math></inline-formula>, as a free parameter, we find indication of a violation of the assumptions. Finally, we compare frequentist and Bayesian constraints of these models. Our results motivate care when using the graphical profile likelihood method in cosmology.

Through gravitational lensing, galaxy clusters can magnify supernovae (SNe) and create multiple images of the same SN. This enables measurements of cosmological parameters, which will be increasingly important in light of upcoming telescopic surveys. We study the prospects of detecting strongly lensed SNe in cluster fields with the Nancy Grace Roman Space Telescope (Roman)'s High Latitude Time Domain Survey (HLTDS) and the Vera C. Rubin Observatory's Legacy Survey of Space and Time (LSST). We employed two approaches: one focusing on known multiply imaged galaxies behind clusters, along with the SN rates specific to those galaxies, and another based on the expected number of lensed SNe exploding in a given volume behind a galaxy cluster. We collected all the clusters in the literature that feature a well-constrained lens model and multiply imaged galaxies behind clusters with high-quality data for the lensed galaxies. This allowed us to determine the SN rate for each galaxy. We provide predictions for 46 clusters visible to the Vera C. Rubin Observatory, as well as for 9 observable by Roman's HLTDS, depending on whether the clusters fall within the survey's observing field. We predict that the number of multiply imaged SNe discovered by LSST in its first three years is $3.95 \pm 0.89$ from the first approach or $4.94 \pm 1.02$ from the second. For the HLTDS, the expected number of multiply imaged SNe ranges from $0.38 \pm 0.15$ to $5.2 \pm 2.2$, depending on the specific cluster observed, however, the fields to be targeted remain a matter of discussion. We conclude that LSST offers great prospects for detecting multiply imaged SNe. Our predictions are effectively lower limits, as we only considered the most massive and well-studied clusters. We provide a recommendation for HLTDS observing field selection, namely: either MACS J0553.4-3342 or Abell 1758a should be observed by the survey.

During the accretion phase of a core-collapse supernova (SN), dark-photon (DP) cooling can be largest in the gain layer below the stalled shock wave. In this way, it could counteract the usual shock rejuvenation by neutrino energy deposition and thus prevent the explosion. This peculiar energy-loss profile derives from the resonant nature of DP production. The largest cooling and thus strongest constraints obtain for DP masses of 0.1–0.4 MeV, a range corresponding to the photon plasma mass in the gain region. Electron-capture supernovae, once observationally unambiguously identified, could provide strong bounds even down to nearly 0.01 MeV. For a coupling strength so small that neutrino-driven explosions are expected to survive, the DP cooling of the core is too small to modify the neutrino signal, i.e., our new argument supersedes the traditional SN1987A cooling bound.

Feedback from active galactic nuclei (AGN) is crucial for regulating galaxy evolution. Motivated by observations of broad absorption line winds from rapidly accreting supermassive black holes (SMBHs), we introduce the Mistral AGN feedback model, implemented in the Arepo code. Mistral comes in two versions: continuous radial (Mistral-continuous) and stochastic bipolar momentum deposition (Mistral-stochastic). Using the framework of the IllustrisTNG simulations, we explore the effect of Mistral on BH and galaxy properties, through an idealized Milky Way-mass galaxy and cosmological zoom simulations run down to $z=2$. Unlike standard thermal AGN feedback prescriptions, Mistral generates galaxy-scale winds that mimic outflows driven by BH accretion. Mistral-continuous produces short-lived galactic fountains, and is inefficient at regulating the growth of massive galaxies at $z=2$. In contrast, Mistral-stochastic efficiently suppresses star formation in massive galaxies, and reproduces the empirical stellar-to-halo mass and ($z=0$) BH-stellar mass relations. By supporting large-scale ($>50\,\rm kpc$) outflows while simultaneously preventing gas inflows, Mistral-stochastic additionally regulates the cold and hot gas fractions at both galaxy and halo scales. Mistral-stochastic therefore works self-consistently across the halo mass range explored $\left(10^{12}-3\times10^{13}\,\rm M_\odot\right)$, without adopting a SMBH-mass dependent AGN feedback scheme such as the one used in IllustrisTNG. Our model is a promising tool for predicting the impact of radiatively efficient AGN winds on galaxy evolution, and interpreting the growing population of high-redshift galaxies and quasars observed by JWST. This work is part of the "Learning the Universe" collaboration, which aims to infer the physical processes governing the evolution of the Universe.

Precision observations of orbital systems have recently emerged as a promising new means of detecting gravitational waves and ultra-light dark matter, offering sensitivity in new regimes with significant discovery potential. These searches rely critically on precise modeling of the dynamical effects of these signals on the observed system; however, previous analyses have mainly only relied on the secularly-averaged part of the response. We introduce here a fundamentally different approach that allows for a fully time-resolved description of the effects of oscillatory metric perturbations on orbital dynamics. We find that gravitational waves and ultra-light dark matter can induce large oscillations in the orbital parameters of realistic binaries, enhancing the sensitivity to such signals by orders of magnitude compared to previous estimates.

We use galaxy cluster abundance measurements from the South Pole Telescope enhanced by multicomponent matched filter confirmation and complemented with mass information obtained using weak-lensing data from Dark Energy Survey Year 3 (DES Y3) and targeted Hubble Space Telescope observations for probing deviations from the cold dark matter paradigm. Concretely, we consider a class of dark sector models featuring interactions between dark matter (DM) and a dark radiation (DR) component within the framework of the effective theory of structure formation (ETHOS). We focus on scenarios that lead to power suppression over a wide range of scales, and thus can be tested with data sensitive to large scales, as realized, for example, for DM–DR interactions following from an unbroken non-Abelian <inline-formula><mml:math><mml:mi>S</mml:mi><mml:mi>U</mml:mi><mml:mo>(</mml:mo><mml:mi>N</mml:mi><mml:mo>)</mml:mo></mml:math></inline-formula> gauge theory (interaction rate with power-law index <inline-formula><mml:math><mml:mi>n</mml:mi><mml:mo>=</mml:mo><mml:mn>0</mml:mn></mml:math></inline-formula> within the ETHOS parametrization). Cluster abundance measurements are mostly sensitive to the amount of DR interacting with DM, parametrized by the ratio of DR temperature to the cosmic microwave background (CMB) temperature, <inline-formula><mml:math><mml:msub><mml:mi>ξ</mml:mi><mml:mi>DR</mml:mi></mml:msub><mml:mo>=</mml:mo><mml:msub><mml:mi>T</mml:mi><mml:mi>DR</mml:mi></mml:msub><mml:mo>/</mml:mo><mml:msub><mml:mi>T</mml:mi><mml:mi>CMB</mml:mi></mml:msub></mml:math></inline-formula>. We find an upper limit <inline-formula><mml:math><mml:msub><mml:mi>ξ</mml:mi><mml:mi>DR</mml:mi></mml:msub><mml:mo><</mml:mo><mml:mn>17</mml:mn><mml:mo>%</mml:mo></mml:math></inline-formula> at 95% credibility. When the cluster data are combined with Planck 2018 CMB data along with baryon acoustic oscillation (BAO) measurements we find <inline-formula><mml:math><mml:msub><mml:mi>ξ</mml:mi><mml:mi>DR</mml:mi></mml:msub><mml:mo><</mml:mo><mml:mn>10</mml:mn><mml:mo>%</mml:mo></mml:math></inline-formula>, corresponding to a limit on the abundance of interacting DR that is around 3 times tighter than that from CMB + BAO data alone. We also discuss the complementarity of weak lensing informed cluster abundance studies with probes sensitive to smaller scales, explore the impact on our analysis of massive neutrinos, and comment on a slight preference for the presence of a nonzero interacting DR abundance, which enables a physical solution to the <inline-formula><mml:math><mml:msub><mml:mi>S</mml:mi><mml:mn>8</mml:mn></mml:msub></mml:math></inline-formula> tension.

The Euclid Wide Survey (EWS) is predicted to find approximately 170 000 galaxy-galaxy strong lenses from its lifetime observation of 14 000 deg² of the sky. Detecting this many lenses by visual inspection with professional astronomers and citizen scientists alone is infeasible. As a result, machine learning algorithms, particularly convolutional neural networks (CNNs), have been used as an automated method of detecting strong lenses, and have proven fruitful in finding galaxy-galaxy strong lens candidates, such that the usage of CNNs in lens identification has increased. We identify the major challenge to be the automatic detection of galaxy-galaxy strong lenses while simultaneously maintaining a low false positive rate, thus producing a pure and complete sample of strong lens candidates from Euclid with a limited need for visual inspection. One aim of this research is to have a quantified starting point on the achieved purity and completeness with our current version of CNN-based detection pipelines for the VIS images of EWS. This work is vital in preparing our CNN-based detection pipelines to be able to produce a pure sample of the >100 000 strong gravitational lensing systems widely predicted for Euclid. We select all sources with VIS I_E < 23 mag from the Euclid Early Release Observation imaging of the Perseus field. We apply a range of CNN architectures to detect strong lenses in these cutouts. All our networks perform extremely well on simulated data sets and their respective validation sets. However, when applied to real Euclid imaging, the highest lens purity is just ∼11%. Among all our networks, the false positives are typically identifiable by human volunteers as, for example, spiral galaxies, multiple sources, and artifacts, implying that improvements are still possible, perhaps via a second, more interpretable lens selection filtering stage. There is currently no alternative to human classification of CNN-selected lens candidates. Given the expected ∼10⁵ lensing systems in Euclid, this implies 10⁶ objects for human classification, which while very large is not in principle intractable and not without precedent. ★This paper is published on behalf of the Euclid Consortium.

We address the question whether the magneto-rotational instability (MRI) can operate in the near-surface shear layer (NSSL) of the Sun and how it affects the interaction with the dynamo process. Using hydromagnetic mean-field simulations of $αΩ$-type dynamos in rotating shearing-periodic boxes, we show that for negative shear, the MRI can operate above a certain critical shear parameter. This parameter scales inversely with the equipartition magnetic field strength above which $α$ quenching set in. Like the usual $Ω$ effect, the MRI produces toroidal magnetic field, but in our Cartesian cases it is found to reduce the resulting magnetic field strength and thus to suppress the dynamo process. In view of the application to the solar NSSL, we conclude that the turbulent magnetic diffusivity may be too large for the MRI to be excited and that therefore only the standard $Ω$ effect is expected to operate.

Dark matter (DM) particles can interact with particles of the Standard Model. Although there exist constraints from direct and indirect detection experiments, the dynamical evolution of astrophysical objects could provide a promising probe for these interactions. Obtaining astrophysical predictions is challenging and limited by our ability to simulate scatterings between DM and baryonic particles within N-body and hydrodynamics simulations. We develop a novel scheme that allows simulating these interacting dark matter (IDM) models and accurately accounts for their angular and velocity dependence, as well as the mass ratio between the DM and baryonic scattering partners. To describe DM-baryon interactions, we use an N-body code together with its implementation of smoothed-particle hydrodynamics and meshless finite mass. The interaction itself is realised in a pairwise fashion by creating a virtual scattering partner from the baryonic particle and letting it interact with a DM particle using a scattering routine initially developed for self-interacting dark matter. After the interaction, the virtual particle is rejoined with the baryonic particle, fulfilling energy and momentum conservation. Through several test problems, we demonstrate that we can reproduce their analytic solutions with our IDM scheme. We comment on various numerical aspects and challenges as well as describe the limitations of our numerical scheme. Furthermore, we study the impact of IDM on halo formation with a collapsing overdensity. Overall, it is possible to accurately model IDM within N-body and hydrodynamics simulations, commonly used in astrophysics. In consequence, our scheme allows for making novel predictions and obtaining new constraints of DM-baryon scattering.

The self-organization of proteins into enriched compartments and the formation of complex patterns are crucial processes for life on the cellular level. Liquid-liquid phase separation is one mechanism for forming such enriched compartments. When phase-separating proteins are membrane-bound and locally disturb it, the mechanical response of the membrane mediates interactions between these proteins. How these membrane-mediated interactions influence the steady state of the protein density distribution is thus an important question to investigate in order to understand the rich diversity of protein and membrane-shape patterns present at the cellular level. This work starts with a widely used model for membrane-bound phase-separating proteins. We numerically solve our system to map out its phase space and perform a careful, systematic expansion of the model equations to characterize the phase transitions through linear stability analysis and free energy arguments. We observe that the membrane-mediated interactions, due to their long-range nature, are capable of qualitatively altering the equilibrium state of the proteins. This leads to arrested coarsening and length-scale selection instead of simple demixing and complete coarsening. In this study, we unambiguously show that long-range membrane-mediated interactions lead to pattern formation in a system that otherwise would not do so. This work provides a basis for further systematic study of membrane-bound pattern-forming systems.

In the presence of a weak gravitational wave (GW) background, astrophysical binary systems act as high-quality resonators, with efficient transfer of energy and momentum between the orbit and a harmonic GW leading to potentially detectable orbital perturbations. In this work, we develop and apply a novel modeling and analysis framework that describes the imprints of GWs on binary systems in a fully time-resolved manner to study the sensitivity of lunar laser ranging, satellite laser ranging, and pulsar timing to both resonant and nonresonant GW backgrounds. We demonstrate that optimal data collection, modeling, and analysis lead to projected sensitivities which are orders of magnitude better than previously appreciated possible, opening up a new possibility for probing the physics-rich but notoriously challenging to access $μ\mathrm{Hz}$ frequency GWs. We also discuss improved prospects for the detection of the stochastic fluctuations of ultra-light dark matter, which may analogously perturb the binary orbits.

The ultra-hot Jupiter (UHJ) TOI-2109b marks the lower edge of the equilibrium temperature gap between 3500 K and 4500 K, an unexplored thermal regime that separates KELT-9b, the hottest planet yet discovered, from all other currently known gas giants. To study the structure of TOI-2109b's atmosphere, we obtained high-resolution emission spectra of both the planetary day- and nightsides with CARMENES and CRIRES$^+$. By applying the cross-correlation technique, we identified the emission signatures of Fe I and CO, as well as a thermal inversion layer in the dayside atmosphere; no significant H$_2$O signal was detected from the dayside. None of the analyzed species were detectable from the nightside atmosphere. We applied a Bayesian retrieval framework that combines high-resolution spectroscopy with photometric measurements to constrain the dayside atmospheric parameters and derive upper limits for the nightside hemisphere. The dayside thermal inversion extends from 3200 K to 4600 K, with an atmospheric metallicity consistent with that of the host star (0.36 dex). Only weak constraints could be placed on the C/O ratio ($>$ 0.15). The retrieved spectral line broadening is consistent with tidally locked rotation, indicating the absence of strong dynamical processes. An upper temperature limit of 2400 K and a maximum atmospheric temperature gradient of 700 K/log bar could be derived for the nightside. Comparison of the retrieved dayside T-p profile with theoretical models, the absence of strong atmospheric dynamics, and significant differences in the thermal constraints between the day- and nightside hemispheres suggest a limited heat transport efficiency across the planetary atmosphere. Overall, our results place TOI-2109b in a transitional regime between the UHJs below the thermal gap, which show both CO and H$_2$O emission lines, and KELT-9b, where molecular features are largely absent.

We update the Standard Model (SM) predictions for the lifetimes of the B⁺, B_d and B_s mesons within the heavy quark expansion (HQE), including the recently determined NNLO-QCD corrections to non-leptonic decays of the free b-quark. In addition, we update the HQE predictions for the lifetime ratios τ (B⁺)/τ (B_d) and τ (B_s)/τ (B_d), and provide new results for the semileptonic branching fractions of the three mesons entirely within the HQE. We obtain a considerable improvement of the theoretical uncertainties, mostly due to the reduction of the renormalisation scale dependence when going from LO to NNLO, and for all the observables considered, we find good agreement, within uncertainties, between the HQE predictions and the corresponding experimental data. Our results read, respectively, Γ(B⁺) = <inline-formula><mml:math><mml:msubsup><mml:mn>0.587</mml:mn><mml:mrow><mml:mo>‑</mml:mo><mml:mn>0.035</mml:mn></mml:mrow><mml:mrow><mml:mo>+</mml:mo><mml:mn>0.025</mml:mn></mml:mrow></mml:msubsup></mml:math></inline-formula> ps^‑1, Γ(B_d) = <inline-formula><mml:math><mml:msubsup><mml:mn>0.636</mml:mn><mml:mrow><mml:mo>‑</mml:mo><mml:mn>0.037</mml:mn></mml:mrow><mml:mrow><mml:mo>+</mml:mo><mml:mn>0.028</mml:mn></mml:mrow></mml:msubsup></mml:math></inline-formula> ps^‑1, Γ(B_s) = <inline-formula><mml:math><mml:msubsup><mml:mn>0.628</mml:mn><mml:mrow><mml:mo>‑</mml:mo><mml:mn>0.035</mml:mn></mml:mrow><mml:mrow><mml:mo>+</mml:mo><mml:mn>0.027</mml:mn></mml:mrow></mml:msubsup></mml:math></inline-formula> ps^‑1, for the total decay widths, τ (B⁺)/τ (B_d) = <inline-formula><mml:math><mml:msubsup><mml:mn>1.081</mml:mn><mml:mrow><mml:mo>‑</mml:mo><mml:mn>0.016</mml:mn></mml:mrow><mml:mrow><mml:mo>+</mml:mo><mml:mn>0.014</mml:mn></mml:mrow></mml:msubsup></mml:math></inline-formula>, τ (B_s)/τ (B_d) = <inline-formula><mml:math><mml:msubsup><mml:mn>1.013</mml:mn><mml:mrow><mml:mo>‑</mml:mo><mml:mn>0.007</mml:mn></mml:mrow><mml:mrow><mml:mo>+</mml:mo><mml:mn>0.007</mml:mn></mml:mrow></mml:msubsup></mml:math></inline-formula>, for the lifetime ratios, and <inline-formula><mml:math><mml:msub><mml:mi>B</mml:mi><mml:mi>sl</mml:mi></mml:msub><mml:mfenced><mml:msup><mml:mi>B</mml:mi><mml:mo>+</mml:mo></mml:msup></mml:mfenced></mml:math></inline-formula> = <inline-formula><mml:math><mml:mfenced><mml:msubsup><mml:mn>11.46</mml:mn><mml:mrow><mml:mo>‑</mml:mo><mml:mn>0.32</mml:mn></mml:mrow><mml:mrow><mml:mo>+</mml:mo><mml:mn>0.47</mml:mn></mml:mrow></mml:msubsup></mml:mfenced><mml:mo>%</mml:mo></mml:math></inline-formula>, <inline-formula><mml:math><mml:msub><mml:mi>B</mml:mi><mml:mi>sl</mml:mi></mml:msub><mml:mfenced><mml:msub><mml:mi>B</mml:mi><mml:mi>d</mml:mi></mml:msub></mml:mfenced></mml:math></inline-formula> = <inline-formula><mml:math><mml:mfenced><mml:msubsup><mml:mn>10.57</mml:mn><mml:mrow><mml:mo>‑</mml:mo><mml:mn>0.27</mml:mn></mml:mrow><mml:mrow><mml:mo>+</mml:mo><mml:mn>0.47</mml:mn></mml:mrow></mml:msubsup></mml:mfenced><mml:mo>%</mml:mo></mml:math></inline-formula>, <inline-formula><mml:math><mml:msub><mml:mi>B</mml:mi><mml:mi>sl</mml:mi></mml:msub><mml:mfenced><mml:msub><mml:mi>B</mml:mi><mml:mi>s</mml:mi></mml:msub></mml:mfenced></mml:math></inline-formula> = <inline-formula><mml:math><mml:mfenced><mml:msubsup><mml:mn>10.52</mml:mn><mml:mrow><mml:mo>‑</mml:mo><mml:mn>0.29</mml:mn></mml:mrow><mml:mrow><mml:mo>+</mml:mo><mml:mn>0.50</mml:mn></mml:mrow></mml:msubsup></mml:mfenced><mml:mo>%</mml:mo></mml:math></inline-formula>, for the semileptonic branching ratios. Finally, we also provide an outlook for further improvements of the HQE determinations of the B-meson decay widths and of their ratios.

The M-theoretic emergence proposal claims that in an isotropic decompactification limit to M-theory the full effective action is generated via quantum effects by integrating out only the light towers of states of the theory. In the BPS particle sector, these include transversally wrapped $M2$- and $M5$-branes possibly carrying Kaluza-Klein momentum. This implies that a longitudinally wrapped $M5$-brane, i.e. a wrapped $D4$-brane, is not to be included in emergence computations. In this work we collect explicit evidence supporting this point by examining an $F^4$ gauge coupling in six dimensions, making use of the duality between heterotic string theory on $T^4$ and strongly coupled type IIA on K3. In this instance, the M-theoretic emergence proposal can be viewed as a tool for making predictions for the microscopic behavior of string theoretic amplitudes.

We compute differential distributions for Drell–Yan processes at the LHC and the Tevatron colliders at next-to-next-to-leading order in perturbative QCD, including fiducial cuts on the decay leptons in the final state. The comparison of predictions obtained with four different codes shows excellent agreement, once linear power corrections from the fiducial cuts are included in those codes that rely on phase-space slicing subtraction schemes. For Z-boson production we perform a detailed study of the symmetric cuts on the transverse momenta of the decay leptons. Predictions at fixed order in perturbative QCD for those symmetric cuts, typically imposed in experiments, suffer from an instability. We show how this can be remedied by an all-order resummation of the fiducial transverse momentum spectrum, and we comment on the choice of cuts for future experimental analyses.

In this paper, the first in a series, we present a new theoretical model for the global structure and dissipation of relativistically magnetized collisionless shock waves. Quite remarkably, we find that in contrast to unmagnetized shocks, the leading energy dissipation channel does not involve collective plasma interactions. Rather, it is a consequence of nonlinear particle dynamics. We demonstrate that the kinetic-scale shock transition can be modeled as a stationary system consisting of a large set of cold beams coupled through the magnetic field. The fundamental mechanism governing shock dissipation relies on the onset of chaos in orbital dynamics within quasiperiodic solitonic structures. We discuss the impact of upstream temperature and magnetization on the shock profile, recovering the magnetic field compression, downstream velocities, and heating expected from the Rankine-Hugoniot jump conditions. We deduce a rate of entropy generation from the spectrum of Lyapunov exponents and discuss the thermalization of the beam distribution. Our model provides a general framework to study magnetized collisionless shock structures.

The authors present a new method to analytically prove global stability in ghost‑ridden dynamical systems. The proposal encompasses all prior results and consequentially extends them. In particular, it is shown that stability can follow from a conserved quantity that is unbounded from below, contrary to expectation. Novel examples illustrate all of the results. The findings take root on a careful examination of the literature, here comprehensively reviewed for the first time. This work lays the mathematical basis for ulterior extensions to field theory and quantization, and it constitutes a gateway for inter‑disciplinary research in dynamics and integrability.

Quasi-periodic eruptions (QPEs) are rapid, recurring X-ray bursts from supermassive black holes, believed to result from interactions between accretion disks and surrounding matter. The galaxy SDSS1335+0728, previously stable for two decades, exhibited an increase in optical brightness in December 2019, followed by persistent active galactic nucleus (AGN)-like variability for 5 yr, suggesting the activation of a ~10⁶-M_⊙ black hole. Since February 2024, X-ray emission has been detected, revealing extreme ~4.5-d QPEs with high fluxes and amplitudes, long timescales, large integrated energies and a ~25-d superperiod. Low-significance UV variations are reported, probably related to the long timescales and large radii from which the emission originates. This discovery broadens the possible formation channels for QPEs, suggesting that they are linked not solely to tidal disruption events but more generally to newly formed accretion flows, which we are witnessing in real time in a turn-on AGN candidate.

The Standard Model extended by a real scalar singlet S with an approximate ℤ₂ symmetry offers a minimal framework for realizing electroweak baryogenesis (EWBG) during a first-order electroweak phase transition. In this work, we explore a novel mechanism where spontaneous ℤ₂ breaking enables EWBG via domain walls separating two distinct phases of the S field. These domain walls feature restored (or weakly broken) EW symmetry in their cores and sweep through space, generating the baryon asymmetry below the temperature of EW symmetry breaking. We identify the key conditions for the existence of EW-symmetric domain wall cores and analyze the dynamics required for wall propagation over sufficient spatial volumes. Additionally, we outline the CP-violating sources necessary for baryogenesis under different regimes of domain wall evolution. The parameter space accommodating this mechanism spans singlet masses from sub-eV to 15 GeV, accompanied by a non-vanishing mixing with the Higgs boson. Unlike the standard realization of EWBG in the minimal singlet-extended SM, which is notoriously difficult to test, our scenario can be probed by a wide range of existing and upcoming experiments, including fifth force searches, rare meson decays, and EDM measurements.

Galaxy chemical enrichment mechanisms have primarily been constrained by [α/Fe] and [Fe/H] measurements of individual stars and integrated light from stellar populations. However, such measurements are limited at higher redshifts (z > 1). Recently, we proposed an analogous diagram of the oxygen-to-argon abundance ratio, log(O/Ar), versus Ar abundance, 12+log(Ar/H), as a new diagnostic window for emission nebulae. In this Letter, using line flux measurements including temperature-sensitive auroral lines, we present direct determination of O and Ar abundances in nine star-forming galaxies (SFGs) from JWST/NIRSPEC spectra at z ∼ 1.3–7.7 and two more with Keck/MOSFIRE spectra at z ∼ 2.2. Utilizing their positions on the log(O/Ar) versus 12+log(Ar/H) plane, we present the first inference of galaxy chemical enrichment mechanisms from an ensemble of galaxies. Seven SFGs at z ∼ 1.3–4 are consistent with the Milky Way solar neighborhood galactic chemical enrichment models that are driven by core-collapse and Type Ia supernovae in a self-regulated manner. Such enrichment mechanisms thus occur at least out to z ∼ 4. However, four higher-redshift SFGs (z ∼ 3.6–7.7) have lower log(O/Ar) values, revealing potentially different enrichment paths becoming important at z > 3.6. Such log(O/Ar) values may be caused by physical mechanisms such as rapid but intermittent star formation and/or additional enrichment sources. This new diagnostic window for SFGs enables us to reveal the unique fingerprints of galaxy chemical enrichment out to cosmic dawn.

This paper presents a quantitative analysis of the stellar content in the Local Group dwarf irregular galaxy NGC 6822 by comparing stellar evolution models and observations in color–magnitude diagrams (CMDs) and color–color diagrams (CC-Ds). Our analysis is based on optical ground-based g, r, i photometry, and deep archival Hubble Space Telescope photometry of two fields in the galactic disk. We compared young, intermediate-age, and old stellar populations with isochrones from the BaSTI-IAC library and found that NGC 6822 hosts a quite metal-rich ([Fe/H] = ‑0.7 to ‑0.4) young component with an age ranging from 20–100 Myr. The intermediate-age population experienced a modest chemical enrichment between 4 and 8 Gyr ago, while stars older than 11 Gyr have a low metal abundance ([Fe/H] ∼ ‑1.70). We also identified the asymptotic giant branch (AGB) clump population with a luminosity peak at i ∼ 23.35 mag. Our analysis of both the CMD and the optical–near-IR (NIR)–mid-IR (MIR) CC-Ds of AGB oxygen- and carbon-rich stars, using the PARSEC+COLIBRI isochrones with and without circumstellar dust, reveals that this stellar component exhibits a spread in age from 1–2 Gyr and in metallicity between [Fe/H] = ‑1.30 and ‑1.70. The stellar models we used reproduce very well the two distinct color sequences defined by AGB O- and C-rich stars in the various optical–NIR–MIR CC-Ds, suggesting that they are reliable diagnostics to identify and characterize intermediate-age stellar populations. However, we also find that evolutionary prescriptions in the optical i-(r ‑ i) CMDs predict, at fixed color, systematically lower luminosities than observed AGB stars.

Even in the absence of neutrino masses, a neutrino gas can exhibit a homogeneous flavor instability that leads to a periodic motion known as the fast flavor pendulum. A well-known necessary condition is a crossing of the angular flavor lepton distribution. In an earlier work, some of us showed that homogeneous flavor instabilities also obey a Nyquist criterion, inspired by plasma physics. This condition, while more restrictive than the angular crossing, is only sufficient if the unstable branch of the dispersion relation is bounded by critical points that both lie under the light cone (points with subluminal phase velocity). While the lepton-number angle distribution, assumed to be axially symmetric, easily allows one to determine the real-valued branch of the dispersion relation and to recognize if instead superluminal critical points exist, this graphical method does not translate into a simple instability condition. We discuss the homogeneous mode in the more general context of the dispersion relation for modes with arbitrary wave number and stress that it plays no special role on this continuum, except for its regular but fragile long-term behavior, owed to its many symmetries.

We measured the strange-meson spectrum in the scattering reaction $K^{-}+p \rightarrow K^{-}π^{-}π^{-}+p$ with the COMPASS spectrometer at CERN. Using the world's largest sample of this reaction, we performed a comprehensive partial-wave analysis of the mesonic final state. It substantially extends the strange-meson spectrum covering twelve states with masses up to 2.4 GeV/$c^2$. We observe the first candidate for a crypto-exotic strange meson with $J^{P}=0^{-}$ and find $K_3$ and $K_4$ states consistent with predictions for the ground states.

This paper presents a systematic study of X-ray-selected canonical tidal disruption events (TDEs) discovered in the western Galactic hemisphere of the first two eROSITA all-sky surveys (eRASS1 and eRASS2) performed between Dec 2019 and Dec 2020. We compiled a TDE sample from the catalog of eROSITA's extragalactic transients and variables eRO-ExTra, which includes X-ray sources with a variability significance and fractional amplitude over four between eRASS1 and eRASS2, not associated with known AGNs. Each X-ray source is associated with an optical counterpart from the Legacy Survey DR10. Canonical TDEs were selected based on their X-ray light-curve properties (single flare or decline), soft X-ray spectra ($Γ>3$), and the absence of archival X-ray variability and AGN signatures in their host photometry and spectroscopy. The sample includes 31 X-ray-selected TDE candidates with redshifts of $0.02< z<0.34$ and luminosities of $5.7 \times 10^{41}<L_X<5.3 \times 10^{44}$ erg/s in the 0.2-6.0 keV rest frame, of which 30 are canonical TDEs and one is an off-nuclear TDE candidate. The derived X-ray luminosity function is best fit by a double power law with a luminosity break at $10^{44}$ erg/s, corresponding to the Eddington-limiting prediction. This corresponds to a TDE volumetric rate of $ (2.3^{+1.2}_{-0.9})\times10^{-7}\,Mpc^{-3} yr^{-1}$ ($\approx1.2\times 10^{-5}$ events per galaxy per year). TDE host galaxies show a green-valley overdensity. In addition, 20%, 30%, and 15% of the sample exhibit flares in the optical, mid-infrared (mid-IR), or radio bands, respectively. We discuss the differences between X-ray, optical, and mid-IR TDE populations and the origins of multiwavelength flares in the context of the obscuring envelope and stream-stream collision models. Finally, we highlight TDE subpopulations that are not included in the canonical sample and should be explored in the future.

Dense neutrino gases can exhibit collective flavor instabilities, triggering large flavor conversions that are driven primarily by neutrino-neutrino refraction. One broadly distinguishes between fast instabilities that exist in the limit of vanishing neutrino masses, and slow ones, that require neutrino mass splittings. In a related series of papers, we have shown that fast instabilities result from the resonant growth of flavor waves, in the same way as turbulent electric fields in an unstable plasma. Here we extend this framework to slow instabilities, focusing on the simplest case of an infinitely homogeneous medium with axisymmetric neutrino distribution. The relevant length and time scales are defined by three parameters: the vacuum oscillation frequency ω_E = δm²/2E, the scale of neutrino-neutrino refraction energy <inline-formula><mml:math><mml:mi>μ</mml:mi><mml:mo>=</mml:mo><mml:msqrt><mml:mn>2</mml:mn></mml:msqrt><mml:msub><mml:mi>G</mml:mi><mml:mi>F</mml:mi></mml:msub><mml:mfenced><mml:mrow><mml:msub><mml:mi>n</mml:mi><mml:mi>ν</mml:mi></mml:msub><mml:mo>+</mml:mo><mml:msub><mml:mi>n</mml:mi><mml:mover><mml:mi>ν</mml:mi><mml:mo>¯</mml:mo></mml:mover></mml:msub></mml:mrow></mml:mfenced></mml:math></inline-formula>, and the ratio between lepton and particle number <inline-formula><mml:math><mml:mi>ϵ</mml:mi><mml:mo>=</mml:mo><mml:mfenced><mml:mrow><mml:msub><mml:mi>n</mml:mi><mml:mi>ν</mml:mi></mml:msub><mml:mo>‑</mml:mo><mml:msub><mml:mi>n</mml:mi><mml:mover><mml:mi>ν</mml:mi><mml:mo>¯</mml:mo></mml:mover></mml:msub></mml:mrow></mml:mfenced><mml:mo>/</mml:mo><mml:mfenced><mml:mrow><mml:msub><mml:mi>n</mml:mi><mml:mi>ν</mml:mi></mml:msub><mml:mo>+</mml:mo><mml:msub><mml:mi>n</mml:mi><mml:mover><mml:mi>ν</mml:mi><mml:mo>¯</mml:mo></mml:mover></mml:msub></mml:mrow></mml:mfenced></mml:math></inline-formula>. We distinguish between two very different regimes: (i) For ω_E ≪ μϵ², instabilities occur at small spatial scales of order (μϵ)^‑1 with a time scale of order <inline-formula><mml:math><mml:mi>ϵ</mml:mi><mml:msubsup><mml:mi>ω</mml:mi><mml:mi>E</mml:mi><mml:mrow><mml:mo>‑</mml:mo><mml:mn>1</mml:mn></mml:mrow></mml:msubsup></mml:math></inline-formula>. This novel branch of slow instability arises from resonant interactions with neutrinos moving along the axis of symmetry. (ii) For μϵ² ≪ ω_E ≪ μ, the instability is strongly non-resonant, with typical time and length scales of order <inline-formula><mml:math><mml:mn>1</mml:mn><mml:mo>/</mml:mo><mml:msqrt><mml:mrow><mml:msub><mml:mi>ω</mml:mi><mml:mi>E</mml:mi></mml:msub><mml:mi>μ</mml:mi></mml:mrow></mml:msqrt></mml:math></inline-formula>. Unstable modes interact with all neutrino directions at once, recovering the characteristic scaling of the traditional studies of slow instabilities. In the inner regions of supernovae and neutron-star mergers, the first regime may be more likely to appear, meaning that slow instabilities in this region may have an entirely different character than usually envisaged.

Finding the best parametrization for cosmological models in the absence of first-principle theories is an open question. We propose a data-driven parametrization of cosmological models given by the disentangled "latent" representation of a variational autoencoder (VAE) trained to compress cosmic microwave background (CMB) temperature power spectra. We consider a broad range of <inline-formula><mml:math><mml:mrow><mml:mi>Λ</mml:mi></mml:mrow></mml:math></inline-formula>-cold-dark-matter (<inline-formula><mml:math><mml:mi>λ</mml:mi><mml:mi>CDM</mml:mi></mml:math></inline-formula>) and beyond-<inline-formula><mml:math><mml:mi>Λ</mml:mi><mml:mi>CDM</mml:mi></mml:math></inline-formula> cosmologies with an additional early dark energy (EDE) component. We show that these spectra can be compressed into five (<inline-formula><mml:math><mml:mi>Λ</mml:mi><mml:mi>CDM</mml:mi></mml:math></inline-formula>) or eight (EDE) independent latent parameters, as expected when using temperature power spectra alone, and which reconstruct spectra at an accuracy well within the Planck errors. These latent parameters have a physical interpretation in terms of well-known features of the CMB temperature spectrum: these include the position, height and even-odd modulation of the acoustic peaks, as well as the gravitational lensing effect. The VAE also discovers one latent parameter which entirely isolates the EDE effects from those related to <inline-formula><mml:math><mml:mi>Λ</mml:mi><mml:mi>CDM</mml:mi></mml:math></inline-formula> parameters, thus revealing a previously unknown degree of freedom in the CMB temperature power spectrum. We further showcase how to place constraints on the latent parameters using Planck data as typically done for cosmological parameters, obtaining latent values consistent with previous <inline-formula><mml:math><mml:mi>Λ</mml:mi><mml:mi>CDM</mml:mi></mml:math></inline-formula> and EDE cosmological constraints. Our work demonstrates the potential of a data-driven reformulation of current beyond-<inline-formula><mml:math><mml:mi>Λ</mml:mi><mml:mi>CDM</mml:mi></mml:math></inline-formula> phenomenological models into the independent degrees of freedom to which the data observables are sensitive.

In some scenarios for the early universe, non-relativistic thermal dark matter chemically decouples from the thermal environment once the temperature drops well below the dark matter mass. The value at which the energy density freezes out depends on the underlying model. In a simple setting, we provide a comprehensive study of heavy fermionic dark matter interacting with the light degrees of freedom of a dark thermal sector whose temperature T decreases from an initial value close to the freeze-out temperature. Different temperatures imply different hierarchies of energy scales. By exploiting the methods of non-relativistic effective field theories at finite T, we systematically determine the thermal and in-vacuum interaction rates. In particular, we address the impact of the Debye mass on the bound-state formation cross section and the bound-state dissociation and transition widths, and ultimately on the dark matter relic abundance. We numerically compare the corrections to the present energy density originating from the resummation of Debye mass effects with the corrections coming from a next-to-leading order treatment of the bath-particle interactions. We observe that the fixed-order calculation of the inelastic heavy-light scattering at high temperatures provides a larger dark matter depletion, and hence an undersized yield for given benchmark points in the parameter space, with respect to the calculation where Debye mass effects are resummed.

We extend the multireference covariant density functional theory (MR-CDFT) to describe the low-lying states of the odd-mass nucleus $^{43}$S near the neutron magic number $N=28$ with shape coexistence. The wave functions of the low-lying states are constructed as superpositions of configurations with different intrinsic shapes and $K$ quantum numbers, projected onto good particle numbers and angular momenta. The MR-CDFT successfully reproduces the main features of the low-energy structure in $^{43}$S. Our results indicate that the ground state, $3/2^-_1$, is predominantly composed of the intruder prolate one-quasiparticle (1qp) configuration $\nu1/2^-[321]$. In contrast, the $7/2^-_1$ state is identified as a high-$K$ isomer, primarily built on the prolate 1qp configuration $\nu7/2^-[303]$. Additionally, the $3/2^-_2$ state is found to be an admixture dominated by an oblate configuration with $K^π= 1/2^-$, along with a small contribution from a prolate configuration with $K^π= 3/2^-$. These results demonstrate the capability of MR-CDFT to capture the intricate interplay among shape coexistence, $K$-mixing, and isomerism in the low-energy structure of odd-mass nuclei around $N = 28$.

Historically, various methods have been employed to understand the origin of the elements, including observations of elemental abundances which have been compared to Galactic Chemical Evolution (GCE) models. It is also well known that 1D local thermodynamic equilibrium (LTE) measurements fail to accurately capture elemental abundances. Non-LTE (NLTE) effects may play a significant role, and neglecting them leads to erroneous implications in Galaxy modelling. In this paper, we calculate 3D NLTE abundances of seven key iron-peak and neutron-capture elements (Mn, Co, Ni, Sr, Y, Ba, and Eu) based on carefully assembled 1D LTE literature measurements, and investigate their impact within the context of the OMEGA+ GCE model. Our findings reveal that 3D NLTE abundances are significantly higher for iron-peak elements at [Fe/H] <inline-formula><tex-math id="TM0001" notation="LaTeX">$< -3$</tex-math></inline-formula>, with (for the first time ever) [Ni/Fe] and (confirming previous studies) [Co/Fe] on average reaching 0.6-0.8 dex, and [Mn/Fe] reaching <inline-formula><tex-math id="TM0002" notation="LaTeX">$-0.1$</tex-math></inline-formula> dex, which current 1D core-collapse supernova (CCSN) models cannot explain. We also observe a slightly higher production of neutron-capture elements at low metallicities, with 3D NLTE abundances of Eu being higher by + 0.2 dex at [Fe/H] <inline-formula><tex-math id="TM0003" notation="LaTeX">$= -3$</tex-math></inline-formula>. 3D effects are most significant for iron-peak elements in the very metal-poor regime, with average differences between 3D and 1D NLTE reaching up to 0.15 dex. Thus, ignoring 3D NLTE effects introduces significant biases, so including them should be considered whenever possible.

Aims. We study the individual and cumulative impact of stellar feedback processes on massive black hole (MBH) growth in a simulated low-mass dwarf galaxy. Methods. A suite of high-resolution radiation-hydrodynamic simulations called Noctua is performed, using the ArepoNoctua numerical framework for BHs in galaxy simulations. The chemical evolution of the gas is explicitly modelled in a time-dependent non-equilibrium way. Two types of stellar feedback are considered: individually-traced type II supernova (SNII) explosions, and radiatively transferred (on-the-fly) ionising stellar radiation (ISR) from OB stars. As part of the numerical framework, we develop and apply a novel physically-motivated model for MBH gas accretion, taking into account the angular momentum of the gas in the radiatively efficient regime, to estimate the gas accretion rate from the sub-grid accretion disc. Results. Without any stellar feedback, an initial $10^4~\mathrm{M}_\odot$ MBH is able to steadily grow over time, roughly doubling its mass after 800 Myr. Surprisingly, the growth of the MBH is more than doubled when only ISR feedback is considered, compared to the no stellar feedback run. This is due to the star formation rate (SFR) being highly suppressed (to a similar level or slightly above that when SNII feedback is considered), enabling a higher cumulative net gas inflow onto the MBH from not only the cold neutral- and molecular medium phases, but also the unstable- and warm neutral medium phases. With SNII feedback included, the gas accretion onto the MBH is episodic over time, and is suppressed by more than an order of magnitude already during the first 150 Myr. When combining SNII with ISR feedback, the growth of the MBH remains suppressed due to SNII feedback, but to a lesser extent compared to the SNII-only feedback run, due to a slightly lower SFR, and hence a reduced number of SNII events.

That neutrinos carry a nonvanishing rest mass is evidence of physics beyond the Standard Model of elementary particles. Their absolute mass holds relevance in fields from particle physics to cosmology. We report on the search for the effective electron antineutrino mass with the KATRIN experiment. KATRIN performs precision spectroscopy of the tritium β-decay close to the kinematic endpoint. On the basis of the first five measurement campaigns, we derived a best-fit value of <inline-formula><mml:math><mml:mrow><mml:msubsup><mml:mi>m</mml:mi><mml:mi>ν</mml:mi><mml:mn>2</mml:mn></mml:msubsup><mml:mo>=</mml:mo><mml:mo>‑</mml:mo><mml:msubsup><mml:mrow><mml:mn>0.14</mml:mn></mml:mrow><mml:mrow><mml:mo>‑</mml:mo><mml:mn>0.15</mml:mn></mml:mrow><mml:mrow><mml:mo>+</mml:mo><mml:mn>0.13</mml:mn></mml:mrow></mml:msubsup></mml:mrow></mml:math></inline-formula> eV², resulting in an upper limit of m_ν < 0.45 eV at 90% confidence level. Stemming from 36 million electrons collected in 259 measurement days, a substantial reduction of the background level, and improved systematic uncertainties, this result tightens KATRIN's previous bound by a factor of almost two.

Recent high-resolution observations indicate that the progenitors of globular clusters (GCs) at high redshifts had high average stellar surface densities above $10^5\, \mathrm{M}_\odot\, \mathrm{pc}^{-2}$. Studies of the internal structure and kinematics of the clusters, however, remain out of reach. Numerical simulations are necessary to decipher the origin of the zoo of spatio-kinematic features found in present-day GCs. Here we study star cluster formation in a star-by-star hydrodynamical simulation of a low-metallicity starburst occurring during a merger of two gas-rich dwarf galaxies. The simulation accounts for the multiphase interstellar medium, stellar radiation, winds and supernovae, and the accurate small-scale gravitational dynamics near massive stars. We also include prescriptions for stellar collisions and tidal disruption events by black holes. Gravitationally bound star clusters up to $\sim2\times10^5\, \mathrm{M}_\odot$ form dense with initial half-mass radii of $\sim0.1\unicode{x2013}1\, \mathrm{pc}$. The most massive cluster approaches the observed high-redshift surface densities throughout its hierarchical and dissipative assembly. The cluster also hosts a collisionally growing very massive star of $\sim1000\, \mathrm{M}_\odot$ that will eventually collapse, forming an intermediate mass black hole. The assembly leaves an imprint in the spatio-kinematic structure of the cluster. The younger half of stars is more centrally concentrated, rotates faster, and its velocity distribution is more radially biased at outer radii. The older population is more round in shape, rotates slowly, its velocity distribution is isotropic and its velocity dispersion is higher. These results provide a possible explanation for a subset of multiple population features observed in GCs such as NGC 104/47 Tuc.

Among the well-known methods to approximate derivatives of expectancies computed by Monte-Carlo simulations, averages of pathwise derivatives are often the easiest one to apply. Computing them via algorithmic differentiation typically does not require major manual analysis and rewriting of the code, even for very complex programs like simulations of particle-detector interactions in high-energy physics. However, the pathwise derivative estimator can be biased if there are discontinuities in the program, which may diminish its value for applications. This work integrates algorithmic differentiation into the electromagnetic shower simulation code HepEmShow based on G4HepEm, allowing us to study how well pathwise derivatives approximate derivatives of energy depositions in a sampling calorimeter with respect to parameters of the beam and geometry. We found that when multiple scattering is disabled in the simulation, means of pathwise derivatives converge quickly to their expected values, and these are close to the actual derivatives of the energy deposition. Additionally, we demonstrate the applicability of this novel gradient estimator for stochastic gradient-based optimization in a model example.

We calculate two-loop renormalization group equations (RGEs) in the Standard Model Effective Field Theory (SMEFT) with right-handed neutrinos, i.e., the so-called $ν$SMEFT, up to dimension five. Besides the two-loop RGEs of dimension-five (dim-5) operators, we also present those of the renormalizable couplings, including contributions from dim-5 operators. We check consistency relations among the first and second poles of $\varepsilon \equiv (4-d)/2$ with $d$ being the space-time dimension for all renormalization constants and find that those for lepton doublet and right-handed neutrino wave-function renormalization constants, as well as for renormalization constants of charged-lepton and neutrino Yukawa coupling matrices, do not hold. This leads to divergent RG functions for these fields and Yuwawa coupling matrices. We figure out that such infinite RG functions arise from the non-invariance of fields and Yukawa coupling matrices under field redefinitions, considering that flavor transformations are a kind of linear field redefinitions. Those infinite RG functions will disappear once one restores contributions from the derivative of renormalization constants with respect to the Wilson coefficients of redundant operators or, alternatively, considers the RGEs of flavor invariants, which are physical quantities and remain invariant under field redefinitions.

The R³B (Reactions with Relativistic Radioactive Beams) experiment as a major instrument of the NUSTAR collaboration for the research facility FAIR in Darmstadt is designed for kinematically complete studies of reactions with high-energy radioactive beams. Part of the broad physics program of R³B is to constrain the asymmetry term in the nuclear equation-of-state and hence improve the description of highly asymmetric nuclear matter (e.g., in neutron stars). For a precise determination of the neutron-skin thickness – an observable which is directly correlated with the symmetry energy in theoretical calculations – by measuring absolute fragmentation cross sections, it is essential to quantify the uncertainty and challenge the reaction model under stable conditions. During the successful FAIR Phase-0 campaign of R³B, we precisely measured the energy dependence of total interaction cross sections in ¹²C+¹²C collisions, for a direct comparison with calculations based on the eikonal reaction theory.

The synthesis of life from non-living matter has captivated and divided scientists for centuries. This bold goal aims at unraveling the fundamental principles of life and leveraging its unique features, such as its resilience, sustainability, and ability to evolve. Synthetic life represents more than an academic milestone—it has the potential to revolutionize biotechnology, medicine, and materials science. Although the fields of synthetic biology, systems chemistry, and biophysics have made great strides toward synthetic life, progress has been hindered by social, philosophical, and technical challenges, such as vague goals, misaligned interdisciplinary efforts, and incompletely addressing public and ethical concerns. Our perspective offers a roadmap toward the synthesis of life based on discussions during a 2-week workshop with scientists from around the globe.

We present a formulation of coherent states as of consistent quantum description of classical configurations in the Becchi-Rouet-Stora-Tyutin (BRST)-invariant quantization of electrodynamics. The quantization with proper gauge-fixing is performed on the vacuum of the theory, whereas other backgrounds are obtained as BRST-invariant coherent states. One of the key insights is the possibility of constructing the coherent states of pure-gauge configurations. This provides a coherent state understanding of topologically nontrivial configurations in gauge theories and makes a number of features, such as the suppression of transitions between topologically distinct sectors, very transparent at full quantum level. As an example, we construct the Nielsen-Olesen string as a BRST-invariant coherent state. The Abelian pure-gauge configurations can also be viewed as useful analogs for a set of space-times related by coordinate reparametrizations in general relativity.

Historically, various methods have been employed to understand the origin of the elements, including observations of elemental abundances which have been compared to Galactic Chemical Evolution (GCE) models. It is also well known that 1D Local Thermodynamic Equilibrium (LTE) measurements fail to accurately capture elemental abundances. Non-LTE (NLTE) effects may play a significant role, and neglecting them leads to erroneous implications in galaxy modelling. In this paper, we calculate 3D NLTE abundances of seven key iron-peak and neutron-capture elements (Mn, Co, Ni, Sr, Y, Ba, Eu) based on carefully assembled 1D LTE literature measurements, and investigate their impact within the context of the OMEGA+ GCE model. Our findings reveal that 3D NLTE abundances are significantly higher for iron-peak elements at [Fe/H] <-3, with (for the first time ever) [Ni/Fe] and (confirming previous studies) [Co/Fe] on average reaching 0.6-0.8 dex, and [Mn/Fe] reaching -0.1 dex, which current 1D core-collapse supernova (CCSN) models cannot explain. We also observe a slightly higher production of neutron-capture elements at low metallicities, with 3D NLTE abundances of Eu being higher by +0.2 dex at [Fe/H] =-3. 3D effects are most significant for iron-peak elements in the very metal-poor regime, with average differences between 3D NLTE and 1D NLTE reaching up to 0.15 dex. Thus, ignoring 3D NLTE effects introduces significant biases, so including them should be considered whenever possible.

We introduce a novel orbit superposition method designed to reconstruct the stellar density structure, kinematics, and chemical abundance distribution of the entire Milky Way by leveraging 6D phase-space information from its resolved stellar populations, limited by the spatial coverage of APOGEE DR17.

Central regions of nearby disc galaxies display a large variety of structures in their stellar and gas disc that illustrates the outcome of a complex and dynamic evolution. The most visible central structure inside the bar region is the inner molecular disc (the so-called Central Molecular Zone (CMZ) in the Milky Way). Recent observational campaigns have shown that those inner molecular discs have a typical size ranging from a few hundred parsecs to one kiloparsec and tend to appear at the centre of barred discs. The physical phenomena involved in the building, consumption (e.g., star formation) and long-term evolution of those inner gas structures are still strongly debated. It is commonly accepted that the bar plays a role in the fuelling of gas from the large few kiloparsec scale to the inner molecular disc region. However, the exact physical processes involved in the loss of gas angular momentum (e.g., gravitational torques, shear, feedback) and its transport to the centre are not fully understood. Moreover, inner gas discs are intermediate-scale structures which connect the large kiloparsec scale and the subparsec scale physics (e.g., stellar-driven feedback, magnetic torques) involved in the fuelling of the central supermassive black hole (SMBH). Therefore, those inner discs can be considered as ‘gas reservoirs’ and may be efficient suppliers of material for the flickering of the central black hole, the so-called Active Galactic Nuclei (AGN). [...]

This study presents a novel method using spin quantum sensors to explore temporal variations of fundamental constants, significantly expanding the frequency range and providing constraints on scalar dark matter.

In dense neutrino environments like core-collapse supernovae (CCSNe) and neutron star mergers, neutrinos can undergo fast flavor conversions when their angular distribution of neutrino electron lepton number (<inline-formula><mml:math><mml:mi>ν</mml:mi><mml:mi>ELN</mml:mi></mml:math></inline-formula>) crosses zero along some directions. While previous studies have demonstrated the detection of axisymmetric <inline-formula><mml:math><mml:mi>ν</mml:mi><mml:mi>ELN</mml:mi></mml:math></inline-formula> crossings in these extreme environments, nonaxisymmetric crossings have remained elusive, mostly due to the absence of models for their angular distributions. In this study, we present a pioneering analysis of the detection of nonaxisymmetric <inline-formula><mml:math><mml:mi>ν</mml:mi><mml:mi>ELN</mml:mi></mml:math></inline-formula> crossings using machine learning (ML) techniques. Our ML models are trained on data from two CCSN simulations, one with rotation and one without, where nonaxisymmetric features in neutrino angular distributions play a crucial role. We demonstrate that our ML models achieve detection accuracies exceeding 90%. This is an important improvement, especially considering that a significant portion of <inline-formula><mml:math><mml:mi>ν</mml:mi><mml:mi>ELN</mml:mi></mml:math></inline-formula> crossings in these models eluded detection by earlier methods.

We compute the photon self-energy to three loops in Quantum Electrodynamics. The method of differential equations for Feynman integrals and a complete ϵ-factorization of the former allow us to obtain fully analytical results in terms of iterated integrals involving integration kernels related to a K3 geometry. We argue that our basis has the right properties to be a natural generalization of a canonical basis beyond the polylogarithmic case and we show that many of the kernels appearing in the differential equations, cancel out in the final result to finite order in ϵ. We further provide generalized series expansions that cover the whole kinematic space so that our results for the self-energy may be easily evaluated numerically for all values of the momentum squared. From the local solution at p² = 0, we extract the photon wave function renormalization constant in the on-shell scheme to three loops and confirm its agreement with previously obtained results.

We study the deflection of light rays in a cold, nonmagnetized plasma using the worldline framework. Starting from Synge's Hamiltonian formalism, we construct a position-space action and use it perturbatively to calculate light bending angles. In the homogeneous case, the action reduces to that of a massive particle, allowing us to extract the bending angle of light in the presence of the medium using a well-known analogy. For the inhomogeneous case, we consider a power law model and construct Feynman rules in time to compute the purely plasma-induced corrections to the bending angle at next-to-leading-order.

Perturbative calculations for processes involving heavy flavours can be carried out using two approaches: the massive and the massless schemes. These schemes can also be combined to leverage their respective strengths. Additionally, both massive and massless frameworks can be supplemented by soft-gluon resummation. However, matching resummed calculations across the two schemes presents significant challenges, primarily due to the non-commutativity of the soft and small mass limits. The consistent resummation of mass and soft logarithms has been recently achieved at next-to-leading logarithmic (NLL) accuracy. In this paper, we consider heavy-quark fragmentation functions in electron-positron collisions and we extend this framework to achieve the so-called NLL<inline-formula><mml:math><mml:mmultiscripts><mml:mrow></mml:mrow><mml:mrow></mml:mrow><mml:mo>'</mml:mo></mml:mmultiscripts></mml:math></inline-formula> accuracy, which accounts for finite terms in the soft limit.

Ultra-hot Jupiters, an extreme class of planets not found in our Solar System, provide a unique window into atmospheric processes. The extreme temperature contrasts between their day and night sides pose a fundamental climate puzzle: how is energy distributed? To address this, we must observe the three-dimensional structure of these atmospheres, particularly their vertical circulation patterns that can serve as a testbed for advanced global circulation models, for example, in ref. ¹. Here we show a notable shift in atmospheric circulation in an ultra-hot Jupiter: a unilateral flow from the hot star-facing side to the cooler space-facing side of the planet sits below an equatorial super-rotational jet stream. By resolving the vertical structure of atmospheric dynamics, we move beyond integrated global snapshots of the atmosphere, enabling more accurate identification of flow patterns and allowing for a more nuanced comparison to models. Global circulation models based on first principles struggle to replicate the observed circulation pattern² underscoring a critical gap between theoretical understanding of atmospheric flows and observational evidence. This work serves as a testbed to develop more comprehensive models applicable beyond our Solar System as we prepare for the next generation of giant telescopes.

We summarize the status of the kaon theory 50 years after the seminal paper of Kobayashi and Maskawa [Prog. Theor. Phys. 49, 652 (1973)], who pointed out that six quarks are necessary to have CP violation in the Standard Model (SM) and presented a parametrization of a 3 × 3 unitary matrix that, after the discovery of the charm quark in 1974 and the b quark in 1977, dominated the field of flavor-changing processes. One of the main goals of flavor physics since then has been the determination of the four parameters of this matrix, which we will choose here to be |V_us|, |V_cb|, and the two angles of the unitarity triangle, β and γ, with |V_us| introduced by Cabibbo in 1963. I will summarize the recent strategy for determination of these parameters without new physics (NP) infection. It is based on the conjecture of the absence of relevant NP contributions to ΔF = 2 processes that indeed can be demonstrated by a negative rapid test: the |V_cb|-γ plot. This in turn allows one to obtain SM predictions for rare K and B decays that are the most precise to date. We present strategies for the explanation of the anticipated anomaly in the ratio ɛ'/ɛ and the observed anomalies in b → sμ⁺μ^- transitions that are consistent with our ΔF = 2 conjecture. In particular, the absence of NP in the parameter ɛ_K still allows for significant NP effects in ɛ'/ɛ and in rare kaon decays, moreover, in a correlated manner. Similarly, the absence of NP in ΔM_s combined with anomalies in b → sμ⁺μ^- transitions hints at the presence of right-handed quark currents. We also discuss how the nature of neutrinos, Dirac vs. Majorana ones, can be probed in <inline-formula><tex-math id="TM0001" notation="LaTeX">$K\rightarrow \pi \nu \bar{\nu }$</tex-math></inline-formula> and <inline-formula><tex-math id="TM0002" notation="LaTeX">$B\rightarrow K(K^{*})\nu \bar{\nu }$</tex-math></inline-formula> decays. The present status of the ΔI = 1/2 rule and ɛ'/ɛ is summarized.

We construct the equation of state of hypernuclear matter and study the structure of neutron stars employing a chiral hyperon-nucleon interaction of the Jülich–Bonn group tuned to femtoscopic <inline-formula><mml:math><mml:mrow><mml:mi>Λ</mml:mi><mml:mi>p</mml:mi></mml:mrow></mml:math></inline-formula> data of the ALICE Collaboration, and <inline-formula><mml:math><mml:mrow><mml:mi>Λ</mml:mi><mml:mi>Λ</mml:mi></mml:mrow></mml:math></inline-formula> and <inline-formula><mml:math><mml:mi>Ξ</mml:mi></mml:math></inline-formula>N interactions determined from lattice QCD calculations by the HAL QCD Collaboration that reproduce the femtoscopic <inline-formula><mml:math><mml:mrow><mml:mi>Λ</mml:mi><mml:mi>Λ</mml:mi></mml:mrow></mml:math></inline-formula> and <inline-formula><mml:math><mml:mrow><mml:msup><mml:mi>Ξ</mml:mi><mml:mo>-</mml:mo></mml:msup><mml:mi>p</mml:mi></mml:mrow></mml:math></inline-formula> data. We employ the ab-initio microscopic Brueckner–Hartree–Fock theory extended to the strange baryon sector. A special focus is put on the uncertainties of the hyperon interactions and how they are effectively propagated to the composition, equation of state, mass-radius relation and tidal deformability of neutron stars. To such end, we consider the uncertainty due to the experimental error of the femtoscopic <inline-formula><mml:math><mml:mrow><mml:mi>Λ</mml:mi><mml:mi>p</mml:mi></mml:mrow></mml:math></inline-formula> data used to fix the chiral hyperon-nucleon interaction and the theoretical uncertainty, estimated from the residual cut-off dependence of this interaction. We find that the final maximum mass of a neutron star with hyperons is in the range 1.3–1.4 <inline-formula><mml:math><mml:msub><mml:mi>M</mml:mi><mml:mo>⊙</mml:mo></mml:msub></mml:math></inline-formula>, in agreement with previous works. The hyperon puzzle, therefore, remains still an open issue if only two-body hyperon-nucleon and hyperon-hyperon interactions are considered. Predictions for the tidal deformability of neutron stars with hyperons are found to be in agreement with the observational constraints from the gravitational wave event GW170817 in the mass range 1.1–1.3 <inline-formula><mml:math><mml:msub><mml:mi>M</mml:mi><mml:mo>⊙</mml:mo></mml:msub></mml:math></inline-formula>.

This thesis investigates an interacting dark sector, where dark matter scatters off relativistic dark radiation, analogous to photon-electron interaction. This scenario has the potential to address cosmological tensions. Key results include constraints from full-shape galaxy clustering data, cluster abundance analyses, and forecasts for future galaxy cluster surveys. The thesis also refines the computation of the interaction rate, addressing the divergences and incorporating corrections.

In many quantitative investigations of biological systems, including, e.g., the study of biomolecular interactions, assembly and disassembly, aggregation, micelle and vesicle formation, or drug encapsulation, accurate determination of particle sizes is of key interest. Fluorescence correlation spectroscopy (FCS), with its exceptional sensitivity for molecular diffusion properties, has long been proposed as a valuable method to size small, freely diffusible particles with superior precision. It is conceptually related to the more widespread particle sizing technique dynamic light scattering (DLS) but offers greater selectivity and sensitivity due to the use of fluorescence rather than scattered light. However, in spite of these apparent advantages, FCS has never become established as a biophysical routine for particle sizing. This is due to the fact that sensitivity can, under certain conditions, indeed be disadvantageous, as it renders the technique error prone and overly susceptible to signal disturbances. Here, we discuss the systematic challenges, as well as the advances made over the past decades, to employing FCS in polydisperse samples. The problematic role of large particles, a common issue in DLS and FCS, and the effect of fluorescent labeling are discussed in detail, along with strategies for respective error mitigation in experiments and data analysis. We expect this overview to guide future users in successfully applying FCS to their particle sizing problems in the hope of fostering a more widespread and routine use of FCS-based technology.

Bacterial cell division relies on the Z ring, a cytoskeletal structure that acts as a scaffold for the assembly of the divisome. To date, the detailed mechanisms underlying the assembly and stabilization of the Z ring remain elusive. This study highlights the role of the FtsZ-associated protein (Zap) ZapD in the assembly and stabilization of Z-ring-like structures via filament crosslinking. Using cryo-electron tomography and biochemical analysis, we show that, at equimolar concentrations of ZapD and FtsZ, ZapD induces the formation of toroidal structures composed of short, curved FtsZ filaments that are crosslinked vertically, but also laterally and diagonally. At higher concentrations of ZapD, regularly spaced ZapD dimers crosslink FtsZ filaments from above, resulting in the formation of straight bundles. Despite the simplicity of this reconstituted system, these findings provide valuable insights into the structural organization and stabilization of the Z ring by Zap proteins in bacterial cells, revealing the key role of optimal crosslinking density and geometry in enabling filament curvature and ring formation.

The Fornax cluster is one of the closest X-ray-bright galaxy clusters. Previous observations of the intracluster medium were limited to less than R500. We aim to significantly extend the X-ray coverage. We used data from 5 SRG/eROSITA all-sky surveys and performed a detailed 1- and 2-dimensional X-ray surface brightness analysis, tracing hot gas emission from kpc to Mpc scales with a single instrument. We compared the results to those from a recent numerical simulation of the local Universe (SLOW) and correlated the X-ray emission distribution with that of other tracers, including cluster member galaxies, ultra-compact dwarf galaxies, intracluster globular clusters, and HI-tail galaxies. We detect X-ray emission beyond the virial radius, R100=2.2 deg. In the inner regions within R500, we see previously known features, such as a large-scale spiral-shaped edge; however, we do not find obvious evidence of the bow shock several hundred kpc south of the cluster center predicted by previous numerical simulations of the Fornax cluster. Instead, we discover emission fingers beyond R500 to the west and southeast and excesses that stretch out far beyond the virial radius. They might be due to gas being pushed outward by the previous merger with NGC 1404 or due to warm-hot gas infall along large-scale filaments. Intriguingly, we find the distributions of the other tracers - galaxies and globular clusters - to be correlated with the X-ray-excess regions, favoring the infall scenario. Interestingly, we also discover an apparent bridge of low-surface-brightness emission beyond the virial radius connecting to the Fornax A galaxy group, which is also traced by the member galaxy and globular cluster distribution. The gas distribution in the SLOW simulation shows similar features as those we have discovered with eROSITA. With eROSITA, we witness the growth of a cluster along large-scale filaments.

The basic observables in cosmology are known as in-in correlators. Recent calculations have revealed that in-in correlators in four dimensional de Sitter space exhibit hidden simplicity stemming from a close relation to scattering amplitudes in flat space. In this paper we explain how to make this property manifest by dressing flat space Feynman diagrams with certain auxiliary propagators. These dressing rules hold for any order in perturbation theory and can be derived for a broad range of scalar theories, including those with infrared divergences. In the latter case we show that they reproduce the same infrared divergences predicted by the Schwinger-Keldysh formalism.

We study stellar core growth in simulations of merging massive (<inline-formula><tex-math id="TM0001" notation="LaTeX">$M_\star \gt 10^{11}\, \mathrm{M}_{\odot }$</tex-math></inline-formula>) elliptical galaxies by a supermassive black hole (SMBH) displaced by gravitational wave induced recoil velocity. With controlled, dense sampling of the SMBH recoil velocity, we find the core radius originally formed by SMBH binary scouring can grow by a factor of 2-3 when the recoil velocity exceeds <inline-formula><tex-math id="TM0002" notation="LaTeX">$\sim 50$</tex-math></inline-formula> per cent of the central escape velocity, and the mass deficit grows by up to a factor of <inline-formula><tex-math id="TM0003" notation="LaTeX">$\sim 4$</tex-math></inline-formula>. Using Bayesian inference we predict the distribution of stellar core sizes formed through this process to peak at <inline-formula><tex-math id="TM0004" notation="LaTeX">$\sim 1\, \mathrm{kpc}$</tex-math></inline-formula>. An orbital decomposition of stellar particles within the core reveals that radial orbits dominate over tube orbits when the recoil velocity exceeds the velocity dispersion of the core, whereas tube orbits dominate for the lowest recoil kicks. A change in orbital structure is reflected in the anisotropy parameter, with a central tangential bias present only for recoil velocities less than the local stellar velocity dispersion. Emulating current integral field unit observations of the stellar line-of-sight velocity distribution, we uncover a distinct signature in the Gauss-Hermite symmetric deviation coefficient <inline-formula><tex-math id="TM0005" notation="LaTeX">$h_4$</tex-math></inline-formula> that uniquely constrains the core size due to binary scouring. This signature is insensitive to the later evolution of the stellar mass distribution due to SMBH recoil. Our results provide a novel method to estimate the SMBH recoil magnitude from observations of local elliptical galaxies, and implies these galaxies primarily experienced recoil velocities less than the stellar velocity dispersion of the core.

This study presents a novel method using spin quantum sensors to explore temporal variations of fundamental constants, significantly expanding the frequency range and providing constraints on scalar dark matter.

Understanding the ages of stars is crucial for unraveling the formation history and evolution of our Galaxy. Traditional methods for estimating stellar ages from spectroscopic data often struggle with providing appropriate uncertainty estimations and are severely constrained by the parameter space. In this work, we introduce a new approach using normalizing flows, a type of deep generative model, to estimate stellar ages for evolved stars with improved accuracy and robust uncertainty characterization. The model is trained on stellar masses for evolved stars derived from asteroseismology and predicts the relationship between the carbon and nitrogen abundances of a given star and its age. Unlike standard neural network techniques, normalizing flows enable the recovery of full likelihood distributions for individual stellar ages, offering a richer and more informative perspective on uncertainties. Our method yields age estimations for 378,720 evolved stars and achieves a typical absolute age uncertainty of approximately 2 Gyr. By intrinsically accounting for the coverage and density of the training data, our model ensures that the resulting uncertainties reflect both the inherent noise in the data and the completeness of the sampled parameter space. Applying this method to data from the SDSS-V Milky Way Mapper, we have produced the largest stellar age catalog for evolved stars to date.

We have carried out a systematic search for galaxy-scale lenses exploiting multi-band 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 i-Kron radius above 0.8". 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 (FPR) 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. We carried out a comprehensive multi-stage visual inspection involving eight individuals and identified 95 grade A (average grade G >2.5) and 503 grade B (2.5 >G >1.5) lens candidates, including 92 discoveries 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, help reduce the number of false positives that is the main limitation in lens search to date.

Context. Theoretical models of structure formation predict the presence of a hot gaseous atmosphere around galaxies. While this hot circumgalactic medium (CGM) has been observationally confirmed through UV absorption lines, the detection of its direct X-ray emission remains scarce. Recent results from the eROSITA collaboration have claimed the detection of the CGM out to the virial radius for a stacked sample of Milky Way-mass galaxies. Aims. We investigate theoretical predictions of the intrinsic CGM X-ray surface brightness (SB) using simulated galaxies and connect them to their global properties, such as the gas temperature, hot gas fraction, and stellar mass. Methods. We selected a sample of central galaxies from the ultra-high-resolution cosmological volume (48 cMpc h^‑1) of the Magneticum Pathfinder set of hydrodynamical cosmological simulations. We classified them as star-forming (SF) or quiescent (QU) based on their specific star formation rate (SFR). For each galaxy, we generated X-ray mock data using the X-ray photon simulator PHOX, from which we obtained SB profiles out to the virial radius for different X-ray emitting components; namely, gas, active galactic nuclei (AGNs), and X-ray binaries (XRBs). We fit a β-profile to the gas component of each galaxy and observed trends between its slope and global quantities of the simulated galaxy. Results. We found marginal differences among the average total SB profile in SF and QU galaxies beyond r > 0.05 R_vir. The relative contribution from hot gas exceeds 70% and is non-zero (≲10%) for XRBs in both galaxy types. At small radii (r < 0.05 R_vir), XRBs dominate the SB profile over the hot gas for QU galaxies. We found positive correlations between the galaxies' global properties and the normalization of their SB profiles. The fitted β-profile slope is correlated with the total gas luminosity, which, in turn, shows strong connections to the current accretion rate of the central supermassive black hole (SMBH). We found the halo scaling relations to be consistent with the literature.

We introduce an extension of the evolution mapping framework to cosmological models that include massive neutrinos. The original evolution mapping framework exploits a degeneracy in the linear matter power spectrum when expressed in ${\rm Mpc}$ units, which compresses its dependence on cosmological parameters into those that affect its shape and a single extra parameter $\sigma_{12}$, defined as the RMS linear variance in spheres of radius $12 {\rm Mpc}$. We show that by promoting the scalar amplitude of fluctuations, $A_{\rm s}$, to a shape parameter, we can additionally describe the suppression due to massive neutrinos at any redshift to sub-0.01\% accuracy across a wide range of masses and for different numbers of mass eigenstates. This methodology has been integrated into the public COMET package, enhancing its ability to emulate predictions of state-of-the-art perturbative models for galaxy clustering, such as the effective field theory (EFT) model. Additionally, the updated software now accommodates a broader cosmological parameter space for the emulator, enables the simultaneous generation of multiple predictions to reduce computation time, and incorporates analytic marginalisation over nuisance parameters to expedite posterior estimation. Finally, we explore the impact of different infrared resummation techniques on galaxy power spectrum multipoles, demonstrating that any discrepancies can be mitigated by EFT counterterms without impacting the cosmological parameters.

Solid-state phonon and charge detectors probe the scattering of weakly interacting particles, such as dark matter and neutrinos, through their low recoil thresholds. Recent advancements have pushed sensitivity to eV-scale energy depositions, uncovering previously-unseen low-energy excess backgrounds. While some arise from known processes such as thermal radiation, luminescence, and stress, others remain unexplained. This review examines these backgrounds, their possible origins, and parallels to low-energy effects in solids. Their understanding is essential for interpreting particle interactions at and below the eV-scale.

Dark matter (DM) environments around black holes (BHs) can influence their mergers through dynamical friction, causing gravitational wave (GW) dephasing during the inspiral phase. While this effect is well studied for collisionless dark matter (CDM), it remains unexplored for self-interacting dark matter (SIDM) due to the typically low DM density in SIDM halo cores. In this work, we show that SIDM models with a massive force mediator can support dense enough DM spikes, significantly affecting BH mergers and producing a distinct GW dephasing. Using ${N}$-body simulations, we analyze GW dephasing in binary BH inspirals within CDM and SIDM spikes. By tracking the binary's motion in different SIDM environments, we show that the Laser Interferometer Space Antenna (LISA) can distinguish DM profiles shaped by varying DM interaction strengths, revealing detailed properties of SIDM.

We demonstrate that chiral symmetry breaking occurs in the confining regime of QCD-like theories with <mml:math altimg="si1.svg"><mml:msub><mml:mrow><mml:mi>N</mml:mi></mml:mrow><mml:mrow><mml:mi>c</mml:mi></mml:mrow></mml:msub></mml:math> colors and <mml:math altimg="si2.svg"><mml:msub><mml:mrow><mml:mi>N</mml:mi></mml:mrow><mml:mrow><mml:mi>f</mml:mi></mml:mrow></mml:msub></mml:math> flavors. Our proof is based on a novel strategy, called 'downlifting', by which solutions of the 't Hooft anomaly matching and persistent mass conditions for a theory with <mml:math altimg="si3.svg"><mml:msub><mml:mrow><mml:mi>N</mml:mi></mml:mrow><mml:mrow><mml:mi>f</mml:mi></mml:mrow></mml:msub><mml:mo linebreak="goodbreak" linebreakstyle="after">‑</mml:mo><mml:mn>1</mml:mn></mml:math> flavors are constructed from those of a theory with <mml:math altimg="si2.svg"><mml:msub><mml:mrow><mml:mi>N</mml:mi></mml:mrow><mml:mrow><mml:mi>f</mml:mi></mml:mrow></mml:msub></mml:math> flavors, while <mml:math altimg="si1.svg"><mml:msub><mml:mrow><mml:mi>N</mml:mi></mml:mrow><mml:mrow><mml:mi>c</mml:mi></mml:mrow></mml:msub></mml:math> is fixed. By induction, chiral symmetry breaking is proven for any <mml:math altimg="si22.svg"><mml:msub><mml:mrow><mml:mi>N</mml:mi></mml:mrow><mml:mrow><mml:mi>f</mml:mi></mml:mrow></mml:msub><mml:mo>≥</mml:mo><mml:msub><mml:mrow><mml:mi>p</mml:mi></mml:mrow><mml:mrow><mml:mi>m</mml:mi><mml:mi>i</mml:mi><mml:mi>n</mml:mi></mml:mrow></mml:msub></mml:math> in the confining regime, where <mml:math altimg="si5.svg"><mml:msub><mml:mrow><mml:mi>p</mml:mi></mml:mrow><mml:mrow><mml:mi>m</mml:mi><mml:mi>i</mml:mi><mml:mi>n</mml:mi></mml:mrow></mml:msub></mml:math> is the smallest prime factor of <mml:math altimg="si1.svg"><mml:msub><mml:mrow><mml:mi>N</mml:mi></mml:mrow><mml:mrow><mml:mi>c</mml:mi></mml:mrow></mml:msub></mml:math>. The proof can be extended to <mml:math altimg="si6.svg"><mml:msub><mml:mrow><mml:mi>N</mml:mi></mml:mrow><mml:mrow><mml:mi>f</mml:mi></mml:mrow></mml:msub><mml:mo linebreak="goodbreak" linebreakstyle="after"><</mml:mo><mml:msub><mml:mrow><mml:mi>p</mml:mi></mml:mrow><mml:mrow><mml:mi>m</mml:mi><mml:mi>i</mml:mi><mml:mi>n</mml:mi></mml:mrow></mml:msub></mml:math> under the additional assumption on the absence of phase transitions when quark masses are sent to infinity. Our results do not rely on assumptions on the spectrum of massless bound states other than the fact that they are color-singlet hadrons.

We investigate the energy release in the interacting magnetospheres of binary neutron stars (BNSs) with global 3D force-free electrodynamics simulations. The system dynamics depend on the inclinations χ₁ and χ₂ of the stars' magnetic dipole moments relative to their orbital angular momentum. The simplest aligned configuration (χ₁ = χ₂ = 0^∘) has no magnetic field lines connecting the two stars. Remarkably, it still develops separatrix current sheets warping around each star and a dissipative region at the interface of the two magnetospheres. A Kelvin–Helmholtz (KH)–type instability drives significant dissipation at the magnetospheric interface, generating local Alfvénic turbulence and escaping fast magnetosonic waves. Binaries with inclined magnetospheres release energy in two ways: via KH instability at the interface and via magnetic reconnection flares in the twisted flux bundles connecting the companions. Outgoing compressive waves occur in a broad range of BNS parameters, possibly developing shocks and sourcing fast radio bursts. We discuss implications for X-ray and radio precursors of BNS mergers.

Robust modeling of non-linear scales is critical for accurate cosmological inference in Stage IV surveys. For weak lensing analyses in particular, a key challenge arises from the incomplete understanding of how non-gravitational processes, such as supernovae and active galactic nuclei — collectively known as baryonic feedback — affect the matter distribution. Several existing methods for modeling baryonic feedback treat it independently from the underlying cosmology, an assumption which has been found to be inaccurate by hydrodynamical simulations. In this work, we examine the impact of this coupling between baryonic feedback and cosmology on parameter inference at LSST Y1 precision. We build mock 3×2pt data vectors using the Magneticum suite of hydrodynamical simulations, which span a wide range of cosmologies while keeping subgrid parameters fixed. We perform simulated likelihood analyses for two baryon mitigation techniques: (i) the Principal Component Analysis (PCA) method which identifies eigenmodes for capturing the effect baryonic feedback on the data vector and (ii) HMCODE2020 [1] which analytically models the modification in the matter distribution using a halo model approach. Our results show that the PCA method is more robust than HMCODE2020 with biases in Ω_m-S ₈ up to 0.3σ and 0.6σ, respectively, for large deviations from the baseline cosmology. For HMCODE2020, the bias correlates with the input cosmology while for PCA we find no such correlation.

Cyanopolyynes are among the largest and most commonly observed interstellar complex organic molecules in star-forming regions. They are believed to form primarily in the gas phase, but their formation routes are not well understood. We present a comprehensive study of the gas-phase formation network of cyanobutadiyne, HC<inline-formula><tex-math id="TM0001" notation="LaTeX">$_5$</tex-math></inline-formula>N, based on new theoretical calculations, kinetics experiments, astronomical observations, and astrochemical modelling. We performed new quantum mechanics calculations for six neutral-neutral reactions in order to derive reliable rate coefficients and product branching fractions. We also present new CRESU data on the rate coefficients of three of these reactions (C<inline-formula><tex-math id="TM0002" notation="LaTeX">$_3$</tex-math></inline-formula>N + C<inline-formula><tex-math id="TM0003" notation="LaTeX">$_2$</tex-math></inline-formula>H<inline-formula><tex-math id="TM0004" notation="LaTeX">$_2$</tex-math></inline-formula>, C<inline-formula><tex-math id="TM0005" notation="LaTeX">$_2$</tex-math></inline-formula>H + HC<inline-formula><tex-math id="TM0006" notation="LaTeX">$_3$</tex-math></inline-formula>N, CN + C<inline-formula><tex-math id="TM0007" notation="LaTeX">$_4$</tex-math></inline-formula>H<inline-formula><tex-math id="TM0008" notation="LaTeX">$_2$</tex-math></inline-formula>) obtained at temperatures as low as 24 K. In practice, six out of nine reactions currently used in astrochemical models have been updated in our reviewed network. We also report the tentative detection of the <inline-formula><tex-math id="TM0009" notation="LaTeX">$^{13}$</tex-math></inline-formula>C isotopologues of HC<inline-formula><tex-math id="TM0010" notation="LaTeX">$_5$</tex-math></inline-formula>N in the L1544 prestellar core. We derived a lower limit of <inline-formula><tex-math id="TM0011" notation="LaTeX">$^{12}$</tex-math></inline-formula>C/<inline-formula><tex-math id="TM0012" notation="LaTeX">$^{13}$</tex-math></inline-formula>C > 75 for the HC<inline-formula><tex-math id="TM0013" notation="LaTeX">$_5$</tex-math></inline-formula>N isotopologues, which does not allow to bring new constraints to the HC<inline-formula><tex-math id="TM0014" notation="LaTeX">$_5$</tex-math></inline-formula>N chemistry. Finally, we verified the impact of the revised reactions by running the GRETOBAPE astrochemical model. We found good agreement between the HC<inline-formula><tex-math id="TM0015" notation="LaTeX">$_5$</tex-math></inline-formula>N predicted and observed abundances in cold (<inline-formula><tex-math id="TM0016" notation="LaTeX">$\sim$</tex-math></inline-formula>10 K) objects, demonstrating that HC<inline-formula><tex-math id="TM0017" notation="LaTeX">$_5$</tex-math></inline-formula>N is mainly formed by neutral-neutral reactions in these environments. In warm molecular shocks, instead, the predicted abundances are a factor of ten lower with respect to observed ones. In this environment possessing an higher gas ionization fraction, we speculate that the contribution of ion-neutral reactions could be significant.

A possible way of constructing polylogarithms on Riemann surfaces of higher genera facilitates integration kernels, which can be derived from generating functions incorporating the geometry of the surface. Functional relations among polylogarithms rely on identities for those integration kernels. In this article, we derive identities for Enriquez' meromorphic generating function and investigate the implications for the associated integration kernels. The resulting identities are shown to be exhaustive and therefore reproduce all identities for Enriquez' kernels conjectured in arXiv:2407.11476 recently.

The inner Solar System is depleted in refractory carbon in comparison to the interstellar medium and the depletion likely took place in the protoplanetary disk phase of the Solar System. We study the effect of photolysis of refractory carbon in the upper layers of the protosolar disk and its interplay with dust collisional growth and vertical mixing. We make use of a 1D Monte Carlo model to simulate dust coagulation and vertical mixing. To model the FUV flux of the disk, we use a simple analytical prescription and benchmark it with data from a radiative transfer simulation. We study the effects of fragmentation and bouncing on dust distribution and the propagation of carbon depletion. We find that when bouncing is included, the size distribution is truncated at smaller sizes than fragmentation-limited size distributions but there is a loss of small grains as well. The population of small grains is reduced due to fewer fragmentation events and this reduces the effectiveness of photolysis. We find that dust collisional growth and vertical mixing increase the effectiveness of carbon depletion by efficiently replenishing carbon to the upper regions of the disk with higher FUV flux. It takes around 100-300 kyr to reach the measured carbon abundances at 1 au, depending on the strength of the turbulence in the disk. These timescales are faster than reported by previous studies. Collisional redistribution and turbulent mixing are important aspects of dust evolution that should be included when modeling dust chemistry as they can influence the efficiency of chemical processes. Photolysis, along with another process such as sublimation, most likely played a key role in refractory carbon depletion that we see around us in the inner Solar System.

We present a systematic study of one-loop quantum corrections in scalar effective field theories from a geometric viewpoint, emphasizing the role of field-space curvature and its renormalisation. By treating the scalar fields as coordinates on a Riemannian manifold, we exploit field redefinition invariance to maintain manifest coordinate independence of physical observables. Focusing on the non-linear sigma model (NLSM) and \(\phi^4\) theory, we demonstrate how loop corrections induce momentum- and scale-dependent shifts in the curvature of the field-space manifold. These corrections can be elegantly captured through the recently proposed geometry-kinematics duality, which generalizes the colour-kinematics duality in gauge theories to curved field-space backgrounds. Our results highlight a universal structure emerging in the contractions of Riemann tensors that contribute to renormalisation of the field-space curvature. In particular, we find explicit expressions and a universal structure for the running curvature and Ricci scalar in simple models, illustrating how quantum effects reshape the underlying geometry. This geometric formulation unifies a broad class of scalar EFTs, providing insight into the interplay of curvature, scattering amplitudes, and renormalisation.

This paper presents a quantitative analysis of the stellar content in the Local Group dwarf irregular galaxy NGC 6822 by comparing stellar evolution models and observations in color-magnitude diagrams (CMDs) and color-color diagrams (CC-Ds). Our analysis is based on optical ground-based g,r,i photometry, and deep archive HST photometry of two fields in the galaxy disk. We compared young, intermediate-age, and old stellar populations with isochrones from the BaSTI-IAC library and found that NGC 6822 hosts a quite metal-rich ([Fe/H] = -0.7 to -0.4) young component with an age ranging from 20 to 100 Myr. The intermediate-age population experienced a modest chemical enrichment between 4 and 8 Gyr ago while stars older than 11 Gyr have a low metal abundance ([Fe/H] ~ -1.70). We also identified the AGB clump population with a luminosity peak at i ~ 23.35 mag. Our analysis of both the CMD and the optical-NIR-MIR CC-Ds of AGB oxygen- and carbon-rich stars, using the PARSEC+COLIBRI isochrones with and without circumstellar dust, reveal that this stellar component exhibits a spread in age from 1 to 2 Gyr and in metallicity between [Fe/H]=-1.30 and -1.70. The stellar models we used reproduce very well the two distinct color sequences defined by AGB O- and C-rich stars in the various optical-NIR-MIR CC-Ds, suggesting that they are reliable diagnostics to identify and characterise intermediate-age stellar populations. However, we also find that evolutionary prescriptions in the optical i-(r-i) CMDs predict, at fixed color, systematically lower luminosities than observed AGB stars.

Star clusters can interact and merge in galactic discs, halos, or centers. We present direct N-body simulations of binary mergers of star clusters with M_⋆ = 2.7 × 10⁴ M_⊙ each, using the N-body code BIFROSTwith subsystem regularisation and post-Newtonian dynamics. We include 500 M_⊙ massive black holes (MBHs) in the progenitors to investigate their impact on remnant evolution. The MBHs form hard binaries interacting with stars and stellar black holes (BHs). A few Myr after the cluster merger, this produces sizable populations of runaway stars (~800 with v_ej ≳ 50kms^-1) and stellar BHs (~30) escaping within 100 Myr. The remnants lose ~30% of their BH population and ~3% of their stars, with ~30 stars accelerated to high velocities ≳ 300kms^-1. Comparison simulations of isolated clusters with central hard MBH binaries and cluster mergers without MBHs show that the process is driven by MBH binaries, while those with a single 1000 M_⊙ MBH in isolated or merging clusters produce fewer runaway stars at lower velocities. Low-eccentricity merger orbits yield rotating remnants (v_rot ~ 3kms^-1) , but probing the presence of MBHs via kinematics alone remains challenging. We expect the binary MBHs to merge within a Hubble time, producing observable gravitational-wave (GW) events detectable by future GW detectors such as the Einstein Telescope and LISA. The results suggest that interactions with low-mass MBH binaries formed in merging star clusters are an important additional channel for producing runaway and high-velocity stars, free-floating stellar BHs and compact objects.

Ongoing and upcoming wide-field surveys at different wavelengths will measure the distribution of galaxy clusters with unprecedented precision, demanding accurate models for the two-point correlation function (2PCF) covariance. In this work, we assess a semi-analytical framework for the cluster 2PCF covariance that employs three nuisance parameters to account for non-Poissonian shot noise, residual uncertainties in the halo bias model, and subleading noise terms. We calibrate these parameters on a suite of fast approximate simulations generated by PINOCCHIO as well as full $N$-body simulations from OpenGADGET3. We demonstrate that PINOCCHIO can reproduce the 2PCF covariance measured in OpenGADGET3 at the few percent level, provided the mass functions are carefully rescaled. Resolution tests confirm that high particle counts are necessary to capture shot-noise corrections, especially at high redshifts. We perform the parameter calibration across multiple cosmological models, showing that one of the nuisance parameters, the non-Poissonian shot-noise correction $\alpha$, depends mildly on the amplitude of matter fluctuations $\sigma_8$. In contrast, the remaining two parameters, $\beta$ controlling the bias correction and $\gamma$ controlling the secondary shot-noise correction, exhibit more significant variation with redshift and halo mass. Overall, our results underscore the importance of calibrating covariance models on realistic mock catalogs that replicate the selection function of forthcoming surveys and highlight that approximate methods, when properly tuned, can effectively complement full $N$-body simulations for precision cluster cosmology.

Cosmic shear, galaxy clustering, and the abundance of massive halos each probe the large-scale structure of the Universe in complementary ways. We present cosmological constraints from the joint analysis of the three probes, building on the latest analyses of the lensing-informed abundance of clusters identified by the South Pole Telescope (SPT) and of the auto- and cross-correlation of galaxy position and weak lensing measurements (<inline-formula><mml:math display="inline"><mml:mn>3</mml:mn><mml:mo>×</mml:mo><mml:mn>2</mml:mn><mml:mi>pt</mml:mi></mml:math></inline-formula>) in the Dark Energy Survey (DES). We consider the cosmological correlation between the different tracers and we account for the systematic uncertainties that are shared between the large-scale lensing correlation functions and the small-scale lensing-based cluster mass calibration. Marginalized over the remaining <inline-formula><mml:math display="inline"><mml:mi mathvariant="normal">Λ</mml:mi></mml:math></inline-formula> cold dark matter (<inline-formula><mml:math display="inline"><mml:mi mathvariant="normal">Λ</mml:mi><mml:mi>CDM</mml:mi></mml:math></inline-formula>) parameters (including the sum of neutrino masses) and 52 astrophysical modeling parameters, we measure <inline-formula><mml:math display="inline"><mml:msub><mml:mi mathvariant="normal">Ω</mml:mi><mml:mi mathvariant="normal">m</mml:mi></mml:msub><mml:mo>=</mml:mo><mml:mn>0.300</mml:mn><mml:mo>±</mml:mo><mml:mn>0.017</mml:mn></mml:math></inline-formula> and <inline-formula><mml:math display="inline"><mml:msub><mml:mi>σ</mml:mi><mml:mn>8</mml:mn></mml:msub><mml:mo>=</mml:mo><mml:mn>0.797</mml:mn><mml:mo>±</mml:mo><mml:mn>0.026</mml:mn></mml:math></inline-formula>. Compared to constraints from Planck primary cosmic microwave background (CMB) anisotropies, our constraints are only 15% wider with a probability to exceed of 0.22 (<inline-formula><mml:math display="inline"><mml:mn>1.2</mml:mn><mml:mi>σ</mml:mi></mml:math></inline-formula>) for the two-parameter difference. We further obtain <inline-formula><mml:math display="inline"><mml:msub><mml:mi>S</mml:mi><mml:mn>8</mml:mn></mml:msub><mml:mo>≡</mml:mo><mml:msub><mml:mi>σ</mml:mi><mml:mn>8</mml:mn></mml:msub><mml:mo stretchy="false">(</mml:mo><mml:msub><mml:mi mathvariant="normal">Ω</mml:mi><mml:mi mathvariant="normal">m</mml:mi></mml:msub><mml:mo>/</mml:mo><mml:mn>0.3</mml:mn><mml:msup><mml:mo stretchy="false">)</mml:mo><mml:mn>0.5</mml:mn></mml:msup><mml:mo>=</mml:mo><mml:mn>0.796</mml:mn><mml:mo>±</mml:mo><mml:mn>0.013</mml:mn></mml:math></inline-formula> which is lower than the Planck measurement at the <inline-formula><mml:math display="inline"><mml:mn>1.6</mml:mn><mml:mi>σ</mml:mi></mml:math></inline-formula> level. The combined SPT cluster, DES <inline-formula><mml:math display="inline"><mml:mn>3</mml:mn><mml:mo>×</mml:mo><mml:mn>2</mml:mn><mml:mi>pt</mml:mi></mml:math></inline-formula>, and Planck datasets mildly prefer a nonzero positive neutrino mass, with a 95% upper limit <inline-formula><mml:math display="inline"><mml:mo>∑</mml:mo><mml:msub><mml:mi>m</mml:mi><mml:mi>ν</mml:mi></mml:msub><mml:mo><</mml:mo><mml:mn>0.25</mml:mn><mml:mtext> </mml:mtext><mml:mtext> </mml:mtext><mml:mi>eV</mml:mi></mml:math></inline-formula> on the sum of neutrino masses. Assuming a <inline-formula><mml:math display="inline"><mml:mi>w</mml:mi><mml:mi>CDM</mml:mi></mml:math></inline-formula> model, we constrain the dark energy equation of state parameter <inline-formula><mml:math display="inline"><mml:mi>w</mml:mi><mml:mo>=</mml:mo><mml:mo>-</mml:mo><mml:mn>1.1</mml:mn><mml:msubsup><mml:mn>5</mml:mn><mml:mrow><mml:mo>-</mml:mo><mml:mn>0.17</mml:mn></mml:mrow><mml:mrow><mml:mo>+</mml:mo><mml:mn>0.23</mml:mn></mml:mrow></mml:msubsup></mml:math></inline-formula> and when combining with Planck primary CMB anisotropies, we recover <inline-formula><mml:math display="inline"><mml:mi>w</mml:mi><mml:mo>=</mml:mo><mml:mo>-</mml:mo><mml:mn>1.2</mml:mn><mml:msubsup><mml:mn>0</mml:mn><mml:mrow><mml:mo>-</mml:mo><mml:mn>0.09</mml:mn></mml:mrow><mml:mrow><mml:mo>+</mml:mo><mml:mn>0.15</mml:mn></mml:mrow></mml:msubsup></mml:math></inline-formula>, a <inline-formula><mml:math display="inline"><mml:mn>1.7</mml:mn><mml:mi>σ</mml:mi></mml:math></inline-formula> difference with a cosmological constant. The precision of our results highlights the benefits of multiwavelength multiprobe cosmology and our analysis paves the way for upcoming joint analyses of next-generation datasets.

We investigate cosmological correlators for conformally coupled ϕ⁴ theory in four-dimensional de Sitter space. These in-in correlators differ from scattering amplitudes for massless particles in flat space due to the spacelike structure of future infinity in de Sitter. They also require a regularization which preserves de Sitter-invariance, which makes the flat space limit subtle to define at loop-level. Nevertheless we find that up to two loops, the in-in correlators are structurally simpler than the wave function and have the same transcendentality as flat space amplitudes. Moreover, we show that their loop integrands can be recast in terms of flat space integrands and can be derived from a novel recursion relation.

Neutron supermirrors (SMs) are a crucial part of many scattering and particle physics experiments. So far, Ni(Mo)/Ti SMs have been used in experiments that require to transport a polarized neutron beam due to their lower saturation magnetization compared to Ni/Ti SMs. However, next generation $\beta$ decay experiments require SMs that depolarize below $10^{-4}$ per reflection to reach their targeted precision. The depolarization of a polarized neutron beam due to reflection from Ni(Mo)/Ti SMs has not yet been measured to that precision. Recently developed Cu/Ti SMs with a very low saturation magnetization compared to Ni(Mo)/Ti may serve as an alternative. In this paper, we test the performance of both mirrors. At a first stage, we present four-states polarized neutron reflectivity (PNR) curves of Ni(Mo) and Cu monolayers measured at the neutron reflectometer SuperADAM and perform a full polarization analysis, showing a difference between the magnetic scattering length density (mSLD) of both materials, with Cu having a lower mSLD than Ni(Mo). These results are corroborated with the full polarization analysis of four-states PNR curves of $m=2$ Ni(Mo)/Ti and Cu/Ti SMs. In a second stage, we measured the depolarization ($D$) that a polarized neutron beam suffers after reflection from the same Ni(Mo)/Ti and Cu/Ti SMs by using the Opaque Test Bench setup. We find upper limits for the depolarization of $D_\text{Cu/Ti(4N5)}<7.6\times 10^{-5}$, $D_\text{Ni(Mo)/Ti}<8.5\times 10^{-5}$, and $D_\text{Cu/Ti(2N6)}<6.0\times 10^{-5}$ at the $1\sigma$ confidence level, where (4N5) corresponds to a Ti purity of $99.995\%$ and (2N6) to $99.6\%$. The uncertainties are statistical. These results show that all three SMs are suitable for being used in next generation $\beta$ decay experiments. We found no noticeable dependence of $D$ on the $q$ value or the magnetizing field, in which the samples were placed.

Motivated by JWST observations of dense, clumpy and clustered high redshift star formation, we simulate the hierarchical assembly of nine $M_{\mathrm{cl}}=10^6 M_\odot$ star clusters using the BIFROST N-body code. Our low metallicity models ($0.01Z_\odot$) with post-Newtonian equations of motion for black holes include evolving populations of single, binary and triple stars. Massive stars grow by stellar collisions and collapse into intermediate mass black holes (IMBHs) up to $M_\mathrm{\bullet}\sim6200 M_\odot$, stellar multiplicity boosting the IMBH masses by a factor of $2$--$3$. The IMBHs tidally disrupt (TDE) $\sim50$ stars in $10$ Myr with peak TDE rates of $\Gamma\sim10^{-5}$ yr$^{-1}$ per cluster. These IMBHs are natural seeds for supermassive black holes (SMBHs) and the hierarchical assembly frequently leads to $>2$ SMBH seeds per cluster and their rapid mergers ($t<10$ Myr). We propose that a gravitational wave (GW) driven merger of IMBHs with $1000 M_\odot \lesssim M_\bullet \lesssim 10000 M_\odot$ with comparable masses is a characteristic GW fingerprint of SMBH seed formation at redshifts $z>10$, and IMBH formation in similar environments at lower redshifts. Massive star clusters provide a unique environment for the early Universe GW studies for the next-generation GW observatories including the Einstein Telescope and the Laser Interferometer Space Antenna.