We present UV and/or optical observations and models of SN 2023ixf, a type II supernova (SN) located in Messier 101 at 6.9 Mpc. Early time (flash) spectroscopy of SN 2023ixf, obtained primarily at Lick Observatory, reveals emission lines of H I, He I/II, C IV, and N III/IV/V with a narrow core and broad, symmetric wings arising from the photoionization of dense, close-in circumstellar material (CSM) located around the progenitor star prior to shock breakout. These electron-scattering broadened line profiles persist for ~8 days with respect to first light, at which time Doppler broadened the features from the fastest SN ejecta form, suggesting a reduction in CSM density at r ≳ 10¹⁵ cm. The early time light curve of SN 2023ixf shows peak absolute magnitudes (e.g., M _u = -18.6 mag, M _g = -18.4 mag) that are ≳2 mag brighter than typical type II SNe, this photometric boost also being consistent with the shock power supplied from CSM interaction. Comparison of SN 2023ixf to a grid of light-curve and multiepoch spectral models from the non-LTE radiative transfer code CMFGEN and the radiation-hydrodynamics code HERACLES suggests dense, solar-metallicity CSM confined to r = (0.5-1) × 10¹⁵ cm, and a progenitor mass-loss rate of $\dot{M}={10}^{-2}\,{M}_{\odot }$ yr^-1. For the assumed progenitor wind velocity of v _w = 50 km s^-1, this corresponds to enhanced mass loss (i.e., superwind phase) during the last ~3-6 yr before explosion.

Alkaline vents (AVs) are hypothesized to have been a setting for the emergence of life, by creating strong gradients across inorganic membranes within chimney structures. In the past, three-dimensional chimney structures were formed under laboratory conditions; however, no in situ visualization or testing of the gradients was possible. We develop a quasi–two-dimensional microfluidic model of AVs that allows spatiotemporal visualization of mineral precipitation in low-volume experiments. Upon injection of an alkaline fluid into an acidic, iron-rich solution, we observe a diverse set of precipitation morphologies, mainly controlled by flow rate and ion concentration. Using microscope imaging and pH-dependent dyes, we show that finger-like precipitates can facilitate formation and maintenance of microscale pH gradients and accumulation of dispersed particles in confined geometries. Our findings establish a model to investigate the potential of gradients across a semipermeable boundary for early compartmentalization, accumulation, and chemical reactions at the origins of life.

Galaxy-scale strong lenses in galaxy clusters provide a unique tool to investigate their inner mass distribution and the sub-halo density profiles in the low-mass regime, which can be compared with the predictions from cosmological simulations. We search for galaxy-galaxy strong-lensing systems in HST multi-band imaging of galaxy cluster cores from the CLASH and HFF programs by exploring the classification capabilities of deep learning techniques. Convolutional neural networks are trained utilising highly-realistic simulations of galaxy-scale strong lenses injected into the HST cluster fields around cluster members. To this aim, we take advantage of extensive spectroscopic information on member galaxies in 16 clusters and the accurate knowledge of the deflection fields in half of these from high-precision strong lensing models. Using observationally-based distributions, we sample magnitudes, redshifts and sizes of the background galaxy population. By placing these sources within the secondary caustics associated with cluster galaxies, we build a sample of ~3000 galaxy-galaxy strong lenses which preserve the full complexity of real multi-colour data and produce a wide diversity of strong lensing configurations. We study two deep learning networks processing a large sample of image cutouts in three HST/ACS bands, and we quantify their classification performance using several standard metrics. We find that both networks achieve a very good trade-off between purity and completeness (85%-95%), as well as good stability with fluctuations within 2%-4%. We characterise the limited number of false negatives and false positives in terms of the physical properties of the background sources and cluster members. We also demonstrate the neural networks' high degree of generalisation by applying our method to HST observations of 12 clusters with previously known galaxy-scale lensing systems.

This thesis focuses on two main research topics. Firstly, it explores the strong interaction in the proton-deuteron (p-d) system. This is done by measuring two-body correlations through the femtoscopy technique with p-d pairs in pp collision at LHC. The measured correlation is sensitive to the dynamics of three nucleons and can be explained only by the full three-body calculations. Secondly, it investigates the production of deuterons employing the coalescence model in pp collisions.

We present a new description of cosmological evolution of the primordial magnetic field under the condition that it is non-helical and its energy density is larger than the kinetic energy density. We argue that the evolution can be described by four different regimes, according to whether the decay dynamics is linear or not, and whether the dominant dissipation term is the shear viscosity or the drag force. Using this classification and conservation of the Hosking integral, we present analytic models to adequately interpret the results of various numerical simulations of field evolution with variety of initial conditions. It is found that, contrary to the conventional wisdom, the decay of the field is generally slow, exhibiting the inverse transfer, because of the conservation of the Hosking integral. Using the description proposed here, one can trace the intermediate evolution history of the magnetic field and clarify whether each process governing its evolution is frozen or not. Its applicability to the early cosmology is important, since primordial magnetic fields are sometimes constrained to be quite weak, and multiple regimes including the frozen regime matters for such weak fields.

We investigate the ability of human 'expert' classifiers to identify strong gravitational lens candidates in Dark Energy Survey like imaging. We recruited a total of 55 people that completed more than 25 per cent of the project. During the classification task, we present to the participants 1489 images. The sample contains a variety of data including lens simulations, real lenses, non-lens examples, and unlabelled data. We find that experts are extremely good at finding bright, well-resolved Einstein rings, while arcs with g-band signal to noise less than ~25 or Einstein radii less than ~1.2 times the seeing are rarely recovered. Very few non-lenses are scored highly. There is substantial variation in the performance of individual classifiers, but they do not appear to depend on the classifier's experience, confidence or academic position. These variations can be mitigated with a team of 6 or more independent classifiers. Our results give confidence that humans are a reliable pruning step for lens candidates, providing pure and quantifiably complete samples for follow-up studies.

The constraining power promised by future large-scale structure LSS surveys has driven the development of ever better techniques for extracting cosmological information from those datasets. Increase in the expected number of modes that could be well within the reach of the theory offers an improvement of few orders of magnitude with respect to cosmic microwave background (CMB). This extra information is hidden within the non-linear structures of the LSS. It is necessary to very carefully model different physics at play in order to responsibly deal with the upcoming datasets. Consequently, the main goal of this thesis was to push the development and understanding of such theoretical models for the clustering of the large-scale structure. [...]

Within the framework proposed by Caron-Huot and Wilhelm, we give a recipe for computing infrared anomalous dimensions purely on-shell, efficiently up to two loops in any massless theory. After introducing the general formalism and reviewing the one-loop recipe, we extract a practical formula that relates two-loop infrared anomalous dimensions to certain two- and three-particle phase space integrals with tree-level form factors of conserved operators. We finally provide several examples of the use of the two-loop formula and comment on some of its formal aspects, especially the cancellation of `one-loop squared' spurious terms. The present version of the paper is augmented with a detailed treatment of the structure of infrared divergences in massless theories of scalars and fermions up to two loops. In the calculation we encounter divergent phase space integrals and show in detail how these cancel among each other as required by the finiteness of the anomalous dimension. As a non-trivial check of the method, we also perform the computation with a standard diagrammatic approach, finding perfect agreement.

Modern spectroscopic surveys are mapping the Universe in an unprecedented way. In view of this, cosmic voids constitute promising cosmological laboratories. There are two primary statistics in void studies: (i) the void size function, which quantifies their abundance, and (ii) the void-galaxy cross-correlation function, which characterises the density and velocity fields in their surroundings. Nevertheless, in order to design reliable cosmological tests based on these statistics, it is necessary a complete description of the effects of geometrical (Alcock-Paczynski effect) and dynamical (Kaiser effect) distortions. Observational measurements show prominent anisotropic patterns that lead to biased cosmological constraints if they are not properly modelled. I will present a theoretical framework to address this problematic based on a cosmological and dynamical analysis of the mapping of voids between real and redshift space. In addition, I will present a new fiducial-free cosmological test based on two perpendicular projections of the correlation function which allows us to effectively break degeneracies in the model parameter space and to significantly reduce the number of mock catalogues needed to estimate covariances.

The Cherenkov effect describes the creation of well-defined photon signatures by charged particles traversing a medium faster than the speed of light of the medium. By knowing the momentum of the charged particles, the Cherenkov effect allows the identification of the charged particles. Particle identification is one of the primary reasons for using the Cherenkov effect in large detector systems built for high energy physics. Detector systems such as LHCb at the Large Hadron Collider at CERN and BELLE II at KEKb employ Cherenkov detectors for particle identification. In reverse, this thesis aims to reconstruct a known particle’s momentum by measuring its Cherenkov cone. Such a detector, called inverted RICH, has potential applications in beam diagnostics for high energy physics. This work presents the development, construction, and characterization of the prototype detector for an inverted RICH. The detector uses a Lithium Fluoride crystal (diameter 50 mm, and thickness 20 mm with a high refractive index in the UV). The Cherenkov photons created are converted to electrons in a cesium iodide (CsI) photocathode after being transmitted through a Chromium layer (Cr). The signal is detected by a 10x10 cm 2 resistive strip Micromegas. A high voltage guides the Cherenkov electrons through the Micromegas drift region of the detector while the charged particle creates primary electrons inside the gas-filled detector. In this thesis, different radiator and photocathode materials have been studied and explored using the Geant4 simulation toolkit. LiF and MgF 2 were the most suited radiators for initial studies due to their sizeable refractive index leading to a large photon yield. CsI was the most suitable candidate for the photocathode due to its high peak quantum efficiency of 9 %. Also, the CsI photocathode is easier to use with gaseous detectors compared to, e.g. bialkali. [...]

Experiments of free neutron beta decays can probe the weak interaction structure for tensor and scalar contributions. We can measure such contributions as a shift in the electron energy distribution. This thesis focuses on determining systematic uncertainties and corrections in the measurement with Perkeo III in 2019/20. I present the data analysis of this measurement with the corrections to estimate systematic uncertainties, test hypotheses of their causes, and develop new analysis tools.

The RadMap Telescope is a new radiation-monitoring instrument operating in the U.S. Orbital Segment (USOS) of the International Space Station (ISS). The instrument was commissioned in May 2023 and will rotate through four locations inside American, European, and Japanese modules over a period of about six months. In some locations, it will take data alongside operational, validated detectors for a cross-check of measurements. RadMap's central detector is a finely segmented tracking calorimeter that records detailed depth-dose data relevant to studies of the radiation exposure of the ISS crew. It is also able to record particle-dependent energy spectra of cosmic-ray nuclei with energies up to several hundred MeV per nucleon. A unique feature of the detector is its ability to track nuclei with omnidirectional sensitivity at an angular resolution of two degrees. In this contribution, we present the design and capabilities of the RadMap Telescope and give an overview of the instrument's commissioning on the ISS.

Light (anti-) nuclei are a powerful tool both in collider physics and astrophysics. In searches for new and exotic physics, the expected small astrophysical backgrounds at low energies make these antinuclei ideal probes for, e.g., dark matter. At the same time, their composite structure and small binding energies imply that they can be used in collider experiments to probe the hadronization process and two-particle correlations. For the proper interpretation of such experimental studies, an improved theoretical understanding of (anti-) nuclei production in specific kinematic regions and detector setups is needed. In this work, we develop a coalescence framework for (anti-) deuteron production which accounts for both the emission volume and momentum correlations on an event-by-event basis: While momentum correlations can be provided by event generators, such as PYTHIA, the emission volume has to be derived from semiclassical considerations. Moreover, this framework goes beyond the equal-time approximation, which has been often assumed in femtoscopy experiments and (anti-) nucleus production models until now in small interacting systems. Using PYTHIA 8 as an event generator, we find that the equal-time approximation leads to an error of O (10 %) in low-energy processes like Υ decays, while the errors are negligible at CERN Large Hadron Collider energies. The framework introduced in this work paves the way for tuning event generators to (anti-) nuclei measurements.

Achieving autonomous motion is a central objective in designing artificial cells that mimic biological cells in form and function. Cellular motion often involves complex multiprotein machineries, which are challenging to reconstitute in vitro. Here we achieve persistent motion of cell-sized liposomes. These small artificial vesicles are driven by a direct mechanochemical feedback loop between the MinD and MinE protein systems of Escherichia coli and the liposome membrane. Membrane-binding Min proteins self-organize asymmetrically around the liposomes, which results in shape deformation and generates a mechanical force gradient leading to motion. The protein distribution responds to the deformed liposome shape through the inherent geometry sensitivity of the reaction-diffusion dynamics of the Min proteins. We show that such a mechanochemical feedback loop between liposome and Min proteins is sufficient to drive continuous motion. Our combined experimental and theoretical study provides a starting point for the future design of motility features in artificial cells.

We present the first simulations of core-collapse supernovae in axial symmetry with feedback from fast neutrino flavor conversion (FFC). Our schematic treatment of FFCs assumes instantaneous flavor equilibration under the constraint of lepton-number conservation individually for each flavor. Systematically varying the spatial domain where FFCs are assumed to occur, we find that they facilitate SN explosions in low-mass (9 - 12 M_⊙ ) progenitors that otherwise explode with longer time delays, whereas FFCs weaken the tendency to explode of higher-mass (around 20 M_⊙) progenitors.

Free-floating planets (FFPs) can result from dynamical scattering processes happening in the first few million years of a planetary system's life. Several models predict the possibility, for these isolated planetary-mass objects, to retain exomoons after their ejection. The tidal heating mechanism and the presence of an atmosphere with a relatively high optical thickness may support the formation and maintenance of oceans of liquid water on the surface of these satellites. In order to study the timescales over which liquid water can be maintained, we perform dynamical simulations of the ejection process and infer the resulting statistics of the population of surviving exomoons around FFPs. The subsequent tidal evolution of the moons' orbital parameters is a pivotal step to determine when the orbits will circularize, with a consequential decay of the tidal heating. We find that close-in ($a \lesssim 25$ RJ) Earth-mass moons with carbon dioxide-dominated atmospheres could retain liquid water on their surfaces for long timescales, depending on the mass of the atmospheric envelope and the surface pressure assumed. Massive atmospheres are needed to trap the heat produced by tidal friction that makes these moons habitable. For Earth-like pressure conditions (p0 = 1 bar), satellites could sustain liquid water on their surfaces up to 52 Myr. For higher surface pressures (10 and 100 bar), moons could be habitable up to 276 Myr and 1.6 Gyr, respectively. Close-in satellites experience habitable conditions for long timescales, and during the ejection of the FFP remain bound with the escaping planet, being less affected by the close encounter.

Experimental searches for pure glueball states have proven challenging and so far yielded no results. This is believed to occur because glueballs mix with the ordinary q q bar states with the same quantum numbers. We will discuss an alternative mechanism, the formation of the glueball-meson molecular states. We will argue that the wave functions of already observed excited meson states may contain a significant part due to such molecular states. We discuss the phenomenology of glueball-meson molecules and comment on a possible charmless component of the XYZ states.

We study the effect of super-sample covariance (SSC) on the power spectrum and higher-order statistics; bispectrum, halo mass function, and void size function. We also investigate the effect of SSC on the cross covariance between the statistics. We consider both the matter and halo fields. Higher-order statistics of the large-scale structure contain additional cosmological information beyond the power spectrum and are a powerful tool to constrain cosmology. They are a promising probe for ongoing and upcoming high-precision cosmological surveys such as DESI, PFS, Rubin Observatory LSST, Euclid, SPHEREx, SKA, and Roman Space Telescope. Cosmological simulations used in modeling and validating these statistics often have sizes that are much smaller than the observed Universe. Density fluctuations on scales larger than the simulation box, known as super-sample modes, are not captured by the simulations and in turn can lead to inaccuracies in the covariance matrix. We compare the covariance measured using simulation boxes containing super-sample modes to those without. We also compare with the separate universe approach. We find that while the power spectrum, bispectrum and halo mass function show significant scale- or mass-dependent SSC, the void size function shows relatively small SSC. We also find significant SSC contributions to the cross covariances between the different statistics, implying that future joint analyses will need to carefully take into consideration the effect of SSC. To enable further study of SSC, our simulations have been made publicly available.

Fast radio bursts (FRBs) are short astrophysical transients of extragalactic origin. Their burst signal is dispersed by the free electrons in the large-scale-structure (LSS), leading to delayed arrival times at different frequencies. Another potential source of time delay is the well known Shapiro delay, which measures the space-space and time-time metric perturbations along the line-of-sight. If photons of different frequencies follow different trajectories, i.e. if the universality of free fall guaranteed by the weak equivalence principle (WEP) is violated, they would experience an additional relative delay. This quantity, however, is not observable at the background level as it is not gauge independent, which has led to confusion in previous papers. Instead, an imprint can be seen in the correlation between the time delays of different pulses. In this paper, we derive robust and consistent constraints from twelve localized FRBs on the violation of the WEP in the energy range between 4.6 and 6 meV. In contrast to a number of previous studies, we consider our signal to be not in the model, but in the covariance matrix of the likelihood. To do so, we calculate the covariance of the time delays induced by the free electrons in the LSS, the WEP breaking terms, the Milky Way and host galaxy. By marginalizing both host galaxy contribution and the contribution from the free electrons, we find that the parametrized post-Newtonian parameter γ characterizing the WEP violation must be constant in this energy range to 1 in 10¹³ at 68 per cent confidence. These are the tightest constraints to-date on Δγ in this low-energy range.

We present the first nonlinear lattice simulation of an axion field coupled to a U(1) gauge field during inflation. We use it to fully characterize the statistics of the primordial curvature perturbation ζ . We find high-order statistics to be essential in describing non-Gaussianity of ζ in the linear regime of the theory. On the contrary, non-Gaussianity is suppressed when the dynamics become nonlinear. This relaxes the bounds from overproduction of primordial black holes, allowing for an observable gravitational waves signal at pulsar timing array and interferometer scales. Our work establishes lattice simulations as a crucial tool to study the inflationary epoch and its predictions.

The intrinsic alignment (IA) of observed galaxy shapes with the underlying cosmic web is a source of contamination in weak lensing surveys. Sensitive methods to identify the IA signal will therefore need to be included in the upcoming weak lensing analysis pipelines. Hydrodynamical cosmological simulations allow us to directly measure the intrinsic ellipticities of galaxies, and thus provide a powerful approach to predict and understand the IA signal. Here we employ the novel, large-volume hydrodynamical simulation MTNG740, a product of the MillenniumTNG (MTNG) project, to study the IA of galaxies. We measure the projected correlation functions between the intrinsic shape/shear of galaxies and various tracers of large-scale structure, w_+g, w_+m, w₊₊ over the radial range $r_{\rm p} \in [0.02 , 200]\, h^{-1}{\rm Mpc}$ and at redshifts z = 0.0, 0.5, and 1.0. We detect significant signal-to-noise IA signals with the density field for both elliptical and spiral galaxies. We also find significant intrinsic shear-shear correlations for ellipticals. We further examine correlations of the intrinsic shape of galaxies with the local tidal field. Here we find a significant IA signal for elliptical galaxies assuming a linear model. We also detect a weak IA signal for spiral galaxies under a quadratic tidal torquing model. Lastly, we measure the alignment between central galaxies and their host dark-matter haloes, finding small to moderate misalignments between their principal axes that decline with halo mass.

We present five far- and near-ultraviolet spectra of the Type II plateau supernova, SN 2022acko, obtained 5, 6, 7, 19, and 21 days after explosion, all observed with the Hubble Space Telescope/Space Telescope Imaging Spectrograph. The first three epochs are earlier than any Type II plateau supernova has been observed in the far-ultraviolet revealing unprecedented characteristics. These three spectra are dominated by strong lines, primarily from metals, which contrasts with the featureless early optical spectra. The flux decreases over the initial time series as the ejecta cool and line blanketing takes effect. We model this unique data set with the non-local thermodynamic equilibrium radiation transport code CMFGEN, finding a good match to the explosion of a low-mass red supergiant with energy E _kin = 6 × 10⁵⁰ erg. With these models we identify, for the first time, the ions that dominate the early ultraviolet spectra. We present optical photometry and spectroscopy, showing that SN 2022acko has a peak absolute magnitude of V = - 15.4 mag and plateau length of ~115 days. The spectra closely resemble those of SN 2005cs and SN 2012A. Using the combined optical and ultraviolet spectra, we report the fraction of flux as a function of bluest wavelength on days 5, 7, and 19. We create a spectral time-series of Type II supernovae in the ultraviolet, demonstrating the rapid decline of flux over the first few weeks of evolution. Future observations of Type II supernovae are required to map out the landscape of exploding red supergiants, with and without circumstellar material, which is best revealed in high-quality ultraviolet spectra.

We compute the next-to-leading order (NLO) hard correction to the gluon self-energy tensor with arbitrary soft momenta in a hot and/or dense weakly coupled plasma in Quantum Chromodynamics. Our diagrammatic computations of the two-loop and power corrections are performed within the hard-thermal-loop (HTL) framework and in general covariant gauge, using the real-time formalism. We find that after renormalization our individual results are finite and gauge-dependent, and they reproduce previously computed results in Quantum Electrodynamics in the appropriate limit. Combining our results, we also recover a formerly known gauge-independent matching coefficient and associated screening mass in a specific kinematic limit. Our NLO results supersede leading-order HTL results from the 1980s and pave the way to an improved understanding of the bulk properties of deconfined matter, such as the equation of state.

LiteBIRD is a planned JAXA-led cosmic microwave background (CMB) B-mode satellite experiment aiming for launch in the late 2020s, with a primary goal of detecting the imprint of primordial inflationary gravitational waves. Its current baseline focal-plane configuration includes 15 frequency bands between 40 and 402 GHz, fulfilling the mission requirements to detect the amplitude of gravitational waves with the total uncertainty on the tensor-to-scalar ratio, δr, down to δr < 0.001. A key aspect of this performance is accurate astrophysical component separation, and the ability to remove polarized thermal dust emission is particularly important. In this paper we note that the CMB frequency spectrum falls off nearly exponentially above 300 GHz relative to the thermal dust spectral energy distribution, and a relatively minor high frequency extension can therefore result in even lower uncertainties and better model reconstructions. Specifically, we compared the baseline design with five extended configurations, while varying the underlying dust modeling, in each of which the High-Frequency Telescope (HFT) frequency range was shifted logarithmically toward higher frequencies, with an upper cutoff ranging between 400 and 600 GHz. In each case, we measured the tensor-to-scalar ratio r uncertainty and bias using both parametric and minimum-variance component-separation algorithms. When the thermal dust sky model includes a spatially varying spectral index and temperature, we find that the statistical uncertainty on r after foreground cleaning may be reduced by as much as 30-50% by extending the upper limit of the frequency range from 400 to 600 GHz, with most of the improvement already gained at 500 GHz. We also note that a broader frequency range leads to higher residuals when fitting an incorrect dust model, but also it is easier to discriminate between models through higher χ² sensitivity. Even in the case in which the fitting procedure does not correspond to the underlying dust model in the sky, and when the highest frequency data cannot be modeled with sufficient fidelity and must be excluded from the analysis, the uncertainty on r increases by only about 5% for a 500 GHz configuration compared to the baseline.

In recent years, automatic classifiers of image cutouts (also called "stamps") have been shown to be key for fast supernova discovery. The Vera C. Rubin Observatory will distribute about ten million alerts with their respective stamps each night, enabling the discovery of approximately one million supernovae each year. A growing source of confusion for these classifiers is the presence of satellite glints, sequences of point-like sources produced by rotating satellites or debris. The currently planned Rubin stamps will have a size smaller than the typical separation between these point sources. Thus, a larger field-of-view stamp could enable the automatic identification of these sources. However, the distribution of larger stamps would be limited by network bandwidth restrictions. We evaluate the impact of using image stamps of different angular sizes and resolutions for the fast classification of events (active galactic nuclei, asteroids, bogus, satellites, supernovae, and variable stars), using data from the Zwicky Transient Facility. We compare four scenarios: three with the same number of pixels (small field of view with high resolution, large field of view with low resolution, and a multiscale proposal) and a scenario with the full stamp that has a larger field of view and higher resolution. Compared to small field-of-view stamps, our multiscale strategy reduces misclassifications of satellites as asteroids or supernovae, performing on par with high-resolution stamps that are 15 times heavier. We encourage Rubin and its Science Collaborations to consider the benefits of implementing multiscale stamps as a possible update to the alert specification.

Mergers of galaxy clusters are promising probes of dark matter (DM) physics. For example, an offset between the DM component and the galaxy distribution can constrain DM self-interactions. We investigate the role of the intracluster medium (ICM) and its influence on DM-galaxy offsets in self-interacting dark matter models. To this end, we employ Smoothed Particle Hydrodynamics + N-body simulations to study idealized setups of equal- and unequal-mass mergers with head-on collisions. Our simulations show that the ICM hardly affects the offsets arising shortly after the first pericentre passage compared to DM-only simulations. But later on, e.g. at the first apocentre, the offsets can be amplified by the presence of the ICM. Furthermore, we find that cross-sections small enough not to be excluded by measurements of the core sizes of relaxed galaxy clusters have a chance to produce observable offsets. We found that different DM models affect the DM distribution and also the galaxy and ICM distribution, including its temperature. Potentially, the position of the shock fronts, combined with the brightest cluster galaxies, provides further clues to the properties of DM. Overall our results demonstrate that mergers of galaxy clusters at stages about the first apocentre passage could be more interesting in terms of DM physics than those shortly after the first pericentre passage. This may motivate further studies of mergers at later evolutionary stages.

In recent years, differential equations have become the method of choice to compute multi-loop Feynman integrals. Whenever they can be cast into canonical form, their solution in terms of special functions is straightforward. Recently, progress has been made in understanding the precise canonical form for Feynman integrals involving elliptic polylogarithms. In this article, we make use of an algorithmic approach that proves powerful to find canonical forms for these cases. To illustrate the method, we reproduce several known canonical forms from the literature and present examples where a canonical form is deduced for the first time. Together with this article, we also release an update for INITIAL, a publicly available Mathematica implementation of the algorithm.

The radioactive isotopes of 44Ti and 56Ni are important products of explosive nucleosynthesis, which play a key role for supernova (SN) diagnostics and were detected in several nearby young SN remnants. However, most SN models based on non-rotating single stars predict yields of 44Ti that are much lower than the values inferred from observations. We present, for the first time, the nucleosynthesis yields from a self-consistent three-dimensional (3D) SN simulation of an approximately 19 Msun progenitor star that reaches an explosion energy comparable to that of SN 1987A and that covers the evolution of the neutrino-driven explosion until more than 7 seconds after core bounce. We find a significant enhancement of the Ti/Fe yield compared to recent spherically symmetric (1D) models and demonstrate that the long-time evolution is crucial to understand the efficient production of 44Ti due to the non-monotonic temperature and density histories of ejected mass elements. Additionally, we identify characteristic signatures of the nucleosynthesis in proton-rich ejecta, in particular high yields of 45Sc and 64Zn.

Acceleration processes that occur in astrophysical plasmas produce cosmic rays that are observed on Earth. To study particle acceleration, fully-kinetic particle-in-cell (PIC) simulations are often used as they can unveil the microphysics of energization processes. Tracing of individual particles in PIC simulations is particularly useful in this regard. However, by-eye inspection of particle trajectories includes a high level of bias and uncertainty in pinpointing specific acceleration mechanisms that affect particles. Here we present a new approach that uses neural networks to aid individual particle data analysis. We demonstrate this approach on the test data that consists of 252,000 electrons which have been traced in a PIC simulation of a non-relativistic high Mach number perpendicular shock, in which we observe the two-stream electrostatic Buneman instability to pre-accelerate a portion of electrons to nonthermal energies. We perform classification, regression and anomaly detection by using a Convolutional Neural Network. We show that regardless of how noisy and imbalanced the datasets are, the regression and classification are able to predict the final energies of particles with high accuracy, whereas anomaly detection is able to discern between energetic and non-energetic particles. The methodology proposed may considerably simplify particle classification in large-scale PIC and also hybrid kinetic simulations.

We propose to apply several gradient estimation techniques to enable the differentiation of programs with discrete randomness in High Energy Physics. Such programs are common in High Energy Physics due to the presence of branching processes and clustering-based analysis. Thus differentiating such programs can open the way for gradient based optimization in the context of detector design optimization, simulator tuning, or data analysis and reconstruction optimization. We discuss several possible gradient estimation strategies, including the recent Stochastic AD method, and compare them in simplified detector design experiments. In doing so we develop, to the best of our knowledge, the first fully differentiable branching program.

Supernovae are an important source of energy in the interstellar medium. Young remnants of supernovae have a peak emission in the X-ray region, making them interesting objects for X-ray observations. In particular, the supernova remnant SN1006 is of great interest due to its historical record, proximity and brightness. It has therefore been studied by several X-ray telescopes. Improving the X-ray imaging of this and other remnants is important but challenging as it requires to address a spatially varying instrument response in order to achieve a high signal-to-noise ratio. Here, we use Chandra observations to demonstrate the capabilities of Bayesian image reconstruction using information field theory. Our objective is to reconstruct denoised, deconvolved and spatio-spectral resolved images from X-ray observations and to decompose the emission into different morphologies, namely diffuse and point-like. Further, we aim to fuse data from different detectors and pointings into a mosaic and quantify the uncertainty of our result. Utilizing prior knowledge on the spatial and spectral correlation structure of the two components, diffuse emission and point sources, the presented method allows the effective decomposition of the signal into these. In order to accelerate the imaging process, we introduce a multi-step approach, in which the spatial reconstruction obtained for a single energy range is used to derive an informed starting point for the full spatio-spectral reconstruction. The method is applied to 11 Chandra observations of SN1006 from 2008 and 2012, providing a detailed, denoised and decomposed view of the remnant. In particular, the separated view of the diffuse emission should provide new insights into its complex small-scale structures in the center of the remnant and at the shock front profiles.

We present the first cosmological constraints derived from the analysis of the void size function. This work relies on the final Baryon Oscillation Spectroscopic Survey (BOSS) Data Release 12 (DR12) data set, a large spectroscopic galaxy catalog, ideal for the identification of cosmic voids. We extract a sample of voids from the distribution of galaxies, and we apply a cleaning procedure aimed at reaching high levels of purity and completeness. We model the void size function by means of an extension of the popular volume-conserving model, based on two additional nuisance parameters. Relying on mock catalogs specifically designed to reproduce the BOSS DR12 galaxy sample, we calibrate the extended size function model parameters and validate the methodology. We then apply a Bayesian analysis to constrain the Lambda cold dark matter (ΛCDM) model and one of its simplest extensions, featuring a constant dark energy equation of state parameter, w. Following a conservative approach, we put constraints on the total matter density parameter and the amplitude of density fluctuations, finding Ω_m = 0.29 ± 0.06 and ${\sigma }_{8}={0.79}_{-0.08}^{+0.09}$ . Testing the alternative scenario, we derive w = -1.1 ± 0.2, in agreement with the ΛCDM model. These results are independent and complementary to those derived from standard cosmological probes, opening up new ways to identify the origin of potential tensions in the current cosmological paradigm.

The inner kiloparsec regions surrounding sub-Eddington (luminosity less than 10^-3 in Eddington units, L _Edd) supermassive black holes (BHs) often show a characteristic network of dust filaments that terminate in a nuclear spiral in the central parsecs. Here we study the role and fate of these filaments in one of the least accreting BHs known, M31 (10^-7 L _Edd) using hydrodynamical simulations. The evolution of a streamer of gas particles moving under the barred potential of M31 is followed from kiloparsec distance to the central parsecs. After an exploratory study of initial conditions, a compelling fit to the observed dust/ionized gas morphologies and line-of-sight velocities in the inner hundreds of parsecs is produced. After several million years of streamer evolution, during which friction, thermal dissipation, and self-collisions have taken place, the gas settles into a disk tens of parsecs wide. This is fed by numerous filaments that arise from an outer circumnuclear ring and spiral toward the center. The final configuration is tightly constrained by a critical input mass in the streamer of several 10³ M _☉ (at an injection rate of 10^-4 ${M}_{\odot }\,{{\rm{yr}}}^{-1}$ ); values above or below this lead to filament fragmentation or dispersion respectively, which are not observed. The creation of a hot gas atmosphere in the region of ~10⁶ K is key to the development of a nuclear spiral during the simulation. The final inflow rate at 1 pc from the center is ~1.7 × 10^-7 M _☉ yr^-1, consistent with the quiescent state of the M31 BH.

The circumgalactic medium (CGM) plays a crucial role in galaxy evolution as it fuels star formation, retains metals ejected from the galaxies, and hosts gas flows in and out of galaxies. For Milky Way-type and more-massive galaxies, the bulk of the CGM is in hot phases best accessible at X-ray wavelengths. However, our understanding of the CGM remains largely unconstrained due to its tenuous nature. A promising way to probe the CGM is via X-ray absorption studies. Traditional absorption studies utilize bright background quasars, but this method probes the CGM in a pencil beam, and, due to the rarity of bright quasars, the galaxy population available for study is limited. Large-area, high spectral resolution X-ray microcalorimeters offer a new approach to exploring the CGM in emission and absorption. Here, we demonstrate that the cumulative X-ray emission from cosmic X-ray background sources can probe the CGM in absorption. We construct column density maps of major X-ray ions from the Magneticum simulation and build realistic mock images of nine galaxies to explore the detectability of X-ray absorption lines arising from the large-scale CGM. We conclude that the O VII absorption line is detectable around individual massive galaxies at the 3σ-6σ confidence level. For Milky Way-type galaxies, the O VII and O VIII absorption lines are detectable at the ~ 6σ and ~ 3σ levels even beyond the virial radius when coadding data from multiple galaxies. This approach complements emission studies, does not require additional exposures, and will allow for probing the baryon budget and the CGM at the largest scales.

We show that final state interactions (FSI) within a C P T invariant two-channel framework can enhance the charge-parity (C P ) violation difference between D⁰→π^-π⁺ and D⁰→K^-K⁺ decays up to the current experimental value. This result relies upon (i) the dominant tree level diagram, (ii) the well-known experimental values for the D⁰→π^-π⁺ and D⁰→K^-K⁺ branching ratios, and (iii) the π π →π π and π π →K K scattering data to extract the strong phase difference and inelasticity. Based on well-grounded theoretical properties, we find the sign and bulk value of the Δ A_{C P} and A_{C P}(D⁰→π^-π⁺) recently observed by the LHCb Collaboration.

While the role of local interactions in nonequilibrium phase transitions is well studied, a fundamental understanding of the effects of long-range interactions is lacking. We study the critical dynamics of reproducing agents subject to autochemotactic interactions and limited resources. A renormalization group analysis reveals distinct scaling regimes for fast (attractive or repulsive) interactions; for slow signal transduction, the dynamics is dominated by a diffusive fixed point. Furthermore, we present a correction to the Keller-Segel nonlinearity emerging close to the extinction threshold and a novel nonlinear mechanism that stabilizes the continuous transition against the emergence of a characteristic length scale due to a chemotactic collapse.

We introduce the star formation and supernova (SN) feedback model of the SATIN (Simulating AGNs Through ISM with Non-Equilibrium Effects) project to simulate the evolution of the star forming multiphase interstellar medium (ISM) of entire disc galaxies. This galaxy-wide implementation of a successful ISM feedback model tested in small box simulations naturally covers an order of magnitude in gas surface density, shear and radial motions. It is implemented in the adaptive mesh refinement code RAMSES at a peak resolution of 9 pc. New stars are represented by star cluster (sink) particles with individual SN delay times for massive stars. With SN feedback, cooling, and gravity, the galactic ISM develops a three-phase structure. The star formation rates naturally follow observed scaling relations for the local Milky Way gas surface density. SNe drive additional turbulence in the warm (300 < T < 10⁴ K) gas and increase the kinetic energy of the cold gas, cooling out of the warm phase. The majority of the gas leaving the galactic ISM is warm and hot with mass loading factors of 3 ≤ η ≤ 10 up to h = 5 kpc away from the galaxy. While the hot gas is leaving the system, the warm and cold gas falls back onto the disc in a galactic fountain flow. The inclusion of other stellar feedback processes from massive stars seems to be needed to reduce the rate at which stars form at higher surface densities and to increase/decrease the amount of warm/cold gas.

Astrophysical shocks create cosmic rays by accelerating charged particles to relativistic speeds. However, the relative contribution of various types of shocks to the cosmic ray spectrum is still the subject of ongoing debate. Numerical studies have shown that in the non-relativistic regime, oblique shocks are capable of accelerating cosmic rays, depending on the Alfvénic Mach number of the shock. We now seek to extend this study into the mildly relativistic regime. In this case, dependence of the ion reflection rate on the shock obliquity is different compared to the nonrelativistic regime. Faster relativistic shocks are perpendicular for the majority of shock obliquity angles therefore their ability to initialize efficient DSA is limited. We define the ion injection rate using fully kinetic PIC simulation where we follow the formation of the shock and determine the fraction of ions that gets involved into formation of the shock precursor in the mildly relativistic regime covering a Lorentz factor range from 1 to 3. Then, with this result, we use a combined PIC-MHD method to model the large-scale evolution of the shock with the ion injection recipe dependent on the local shock obliquity. This methodology accounts for the influence of the self-generated or pre-existing upstream turbulence on the shock obliquity which allows study substantially larger and longer simulations compared to classical hybrid techniques.

We return to interpreting the historical SN~1987A neutrino data from a modern perspective. To this end, we construct a suite of spherically symmetric supernova models with the Prometheus-Vertex code, using four different equations of state and five choices of final baryonic neutron-star (NS) mass in the 1.36-1.93 M$_\odot$ range. Our models include muons and proto-neutron star (PNS) convection by a mixing-length approximation. The time-integrated signals of our 1.44 M$_\odot$ models agree reasonably well with the combined data of the four relevant experiments, IMB, Kam-II, BUST, and LSD, but the high-threshold IMB detector alone favors a NS mass of 1.7-1.8 M$_\odot$, whereas Kam-II alone prefers a mass around 1.4 M$_\odot$. The cumulative energy distributions in these two detectors are well matched by models for such NS masses, and the previous tension between predicted mean neutrino energies and the combined measurements is gone, with and without flavor swap. Generally, our predicted signals do not strongly depend on assumptions about flavor mixing, because the PNS flux spectra depend only weakly on antineutrino flavor. While our models show compatibility with the events detected during the first seconds, PNS convection and nucleon correlations in the neutrino opacities lead to short PNS cooling times of 5-9 s, in conflict with the late event bunches in Kam-II and BUST after 8-9 s, which are also difficult to explain by background. Speculative interpretations include the onset of fallback of transiently ejected material onto the NS, a late phase transition in the nuclear medium, e.g., from hadronic to quark matter, or other effects that add to the standard PNS cooling emission and either stretch the signal or provide a late source of energy. More research, including systematic 3D simulations, is needed to assess these open issues.

We derive a minimal basis of kernels furnishing the perturbative expansion of the density contrast and velocity divergence in powers of the initial density field that is applicable to cosmological models with arbitrary expansion history, thereby relaxing the commonly adopted Einstein-de-Sitter (EdS) approximation. For this class of cosmological models, the non-linear kernels are at every order given by a sum of terms, each of which factorizes into a time-dependent growth factor and a wavenumber-dependent basis function. We show how to reduce the set of basis functions to a minimal amount, and give explicit expressions up to order $n=5$. We find that for this minimal basis choice, each basis function individually displays the expected scaling behaviour due to momentum conservation, being non-trivial at $n\geq 4$. This is a highly desirable property for numerical evaluation of loop corrections. In addition, it allows us to match the density field to an effective field theory (EFT) description for cosmologies with an arbitrary expansion history, which we explicitly derive at order four. We evaluate the differences to the EdS approximation for $\Lambda$CDM and $w_0w_a$CDM, paying special attention to the irreducible cosmology dependence that cannot be absorbed into EFT terms for the one-loop bispectrum. Finally, we provide algebraic recursion relations for a special generalization of the EdS approximation that retains its simplicity and is relevant for mixed hot and cold dark matter models.

Mechanisms of nucleic acid accumulation were likely critical to life's emergence in the ferruginous oceans of the early Earth. How exactly prebiotic geological settings accumulated nucleic acids from dilute aqueous solutions, is poorly understood. As a possible solution to this concentration problem, we simulated the conditions of prebiotic low-temperature alkaline hydrothermal vents in co-precipitation experiments to investigate the potential of ferruginous chemical gardens to accumulate nucleic acids via sorption. The injection of an alkaline solution into an artificial ferruginous solution under anoxic conditions (O2 < 0.01% of present atmospheric levels) and at ambient temperatures, caused the precipitation of amakinite (“white rust”), which quickly converted to chloride-containing fougerite (“green rust”). RNA was only extractable from the ferruginous solution in the presence of a phosphate buffer, suggesting RNA in solution was bound to Fe2+ ions. During chimney formation, this iron-bound RNA rapidly accumulated in the white and green rust chimney structure from the surrounding ferruginous solution at the fastest rates in the initial white rust phase and correspondingly slower rates in the following green rust phase. This represents a new mechanism for nucleic acid accumulation in the ferruginous oceans of the early Earth, in addition to wet-dry cycles and may have helped to concentrate RNA in a dilute prebiotic ocean.

Non-thermal emission from relativistic electrons gives insight into the strength and morphology of intra-cluster magnetic fields, as well as providing powerful tracers of structure formation shocks. Emission caused by Cosmic Ray (CR) protons on the other hand still challenges current observations and is therefore testing models of proton acceleration at intra-cluster shocks. Large-scale simulations including the effects of CRs have been difficult to achieve and have been mainly reduced to simulating an overall energy budget, or tracing CR populations in post-processing of simulation output and has often been done for either protons or electrons. We use an efficient on-the-fly Fokker-Planck solver to evolve distributions of CR protons and electrons within every resolution element of our simulation. The solver accounts for CR acceleration at intra-cluster shocks, based on results of recent PIC simulations, re-acceleration due to shocks and MHD turbulence, adiabatic changes and radiative losses of electrons. We apply this model to zoom simulations of galaxy clusters, recently used to show the evolution of the small-scale turbulent dynamo on cluster scales. For these simulations we use a spectral resolution of 48 bins over 6 orders of magnitude in momentum for electrons and 12 bins over 6 orders of magnitude in momentum for protons. We present preliminary results about a possible formation mechanism for Wrong Way Radio Relics in our simulation.

Early dust grain growth in protostellar envelopes infalling on young discs has been suggested in recent studies, supporting the hypothesis that dust particles start to agglomerate already during the Class 0/I phase of young stellar objects (YSOs). If this early evolution were confirmed, it would impact the usually assumed initial conditions of planet formation, where only particles with sizes ≲0.25μm are usually considered for protostellar envelopes. We aim to determine the maximum grain size of the dust population in the envelope of the Class 0/I protostar L1527 IRS, located in the Taurus star-forming region (140 pc). We use Atacama Large millimetre/sub-millimetre Array (ALMA) and Atacama Compact Array (ACA) archival data and present new observations, in an effort to both enhance the signal-to-noise ratio of the faint extended continuum emission and properly account for the compact emission from the inner disc. Using observations performed in four wavelength bands and extending the spatial range of previous studies, we aim to place tight constraints on the spectral (α) and dust emissivity (β) indices in the envelope of L1527 IRS. We find a rather flat α∼ 3.0 profile in the range 50-2000 au. Accounting for the envelope temperature profile, we derive values for the dust emissivity index, 0.9 < β < 1.6, and reveal a tentative, positive outward gradient. This could be interpreted as a distribution of mainly ISM-like grains at 2000 au, gradually progressing to (sub-)millimetre-sized dust grains in the inner envelope, where at R=300 au, β = 1.1 +/- 0.1. Our study supports a variation of the dust properties in the envelope of L1527 IRS. We discuss how this can be the result of in-situ grain growth, dust differential collapse from the parent core, or upward transport of disc large grains.

Complex coacervation describes the liquid-liquid phase separation of oppositely charged polymers. Active coacervates are droplets in which one of the electrolyte's affinity is regulated by chemical reactions. These droplets are particularly interesting because they are tightly regulated by reaction kinetics. For example, they serve as a model for membraneless organelles that are also often regulated by biochemical transformations such as post-translational modifications. They are also a great protocell model or could be used to synthesize life–they spontaneously emerge in response to reagents, compete, and decay when all nutrients have been consumed. However, the role of the unreactive building blocks, e.g., the polymeric compounds, is poorly understood. Here, we show the important role of the chemically innocent, unreactive polyanion of our chemically fueled coacervation droplets. We show that the polyanion drastically influences the resulting droplets′ life cycle without influencing the chemical reaction cycle–either they are very dynamic or have a delayed dissolution. Additionally, we derive a mechanistic understanding of our observations and show how additives and rational polymer design help to create the desired coacervate emulsion life cycles.

We derive a factorization theorem for the Higgs-boson production amplitude in gluon-gluon fusion induced by a light-quark loop, working at next-to-leading power in soft-collinear effective theory. The factorization is structurally similar to that obtained for the h → γγ decay amplitude induced by a light-quark loop, but additional complications arise because of external color charges. We show how the refactorization-based subtraction scheme developed in previous work leads to a factorization theorem free of endpoint divergences. We use renormalization-group techniques to predict the logarithmically enhanced terms in the three-loop gg → h form factor of order α_s³ln^k(−M_h²/m_b² ) with k = 6, 5, 4, 3. We also resum the first three towers of leading logarithms, α_sⁿln2^{n −k}(−M_h²/m_b² ) with k = 0, 1, 2, to all orders of perturbation theory.

Using CaWO$_4$ crystals as cryogenic calorimeters, the CRESST experiment searches for nuclear recoils caused by the scattering of potential Dark Matter particles. A reliable identification of a potential signal crucially depends on an accurate background model. In this work we introduce an improved normalisation method for CRESST's model of the electromagnetic backgrounds. Spectral templates, based on Geant4 simulations, are normalised via a Bayesian likelihood fit to experimental background data. Contrary to our previous work, no assumption of partial secular equilibrium is required, which results in a more robust and versatile applicability. Furthermore, considering the correlation between all background components allows us to explain 82.7% of the experimental background within [1 keV, 40 keV], an improvement of 18.6% compared to our previous method.

We summarize the status of the Kaon Theory 50 years after the seminal paper of Kobayashi and Maskawa who pointed out that six quarks are necessary to have CP violation in the Standard Model (SM) and presented a parametrization of a $3\times 3$ unitary matrix that after the discovery of the charm quark in 1974 and the $b$ quark in 1977 dominated the field of flavour changing processes. One of the main goals of flavour physics since then was 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, $\beta$ and $\gamma$ with $|V_{us}|$ introduced by Cabibbo in 1963. I will summarize 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 $\Delta F=2$ processes that indeed can be demonstrated by a negative rapid test: the $|V_{cb}|-\gamma$ plot. This in turn allows to obtain SM predictions for rare $K$ and $B$ decays that are most precise to date. We present strategies for the explanation of the anticipated anomaly in the ratio $\varepsilon'/\varepsilon$ and the observed anomalies in $b\to s\mu^+\mu^-$ transitions that are consistent with our $\Delta F=2$ conjecture. In particular, the absence of NP in the parameter $\varepsilon_K$, still allows for significant NP effects in $\varepsilon'/\varepsilon$ and in rare Kaon decays, moreover in a correlated manner. Similar the absence of NP in $\Delta M_s$ combined with anomalies in $b\to s\mu^+\mu^-$ transitions hints for the presence of right-handed quark currents. We also discuss how the nature of neutrinos, Dirac vs. Majorana one, can be probed in $K\to\pi\nu\bar\nu$ and $B\to K(K^*)\nu\bar\nu$ decays. The present status of the $\Delta I=1/2$ rule and of $\varepsilon'/\varepsilon$ is summarized.

We present BIFROST, an extended version of the GPU-accelerated hierarchical fourth-order forward symplectic integrator code FROST. BIFROST (BInaries in FROST) can efficiently evolve collisional stellar systems with arbitrary binary fractions up to $f_\mathrm{bin}=100~{{\ \rm per\ cent}}$ by using secular and regularized integration for binaries, triples, multiple systems, or small clusters around black holes within the fourth-order forward integrator framework. Post-Newtonian (PN) terms up to order PN3.5 are included in the equations of motion of compact subsystems with optional three-body and spin-dependent terms. PN1.0 terms for interactions with black holes are computed everywhere in the simulation domain. The code has several merger criteria (gravitational-wave inspirals, tidal disruption events, and stellar and compact object collisions) with the addition of relativistic recoil kicks for compact object mergers. We show that for systems with N particles the scaling of the code remains good up to N_GPU ~ 40 × N/10⁶ GPUs and that the increasing binary fractions up to 100 per cent hardly increase the code running time (less than a factor ~1.5). We also validate the numerical accuracy of BIFROST by presenting a number of star clusters simulations the most extreme ones including a core collapse and a merger of two intermediate mass black holes with a relativistic recoil kick.

Feeding with gas in streams is well established to be an important galaxy growth mechanism. Using an idealized set-up of an isolated galaxy, we study the impact of stream feeding (with 10⁷ M_⊙ Myr^-1 rate) on the star formation and outflows of disc galaxies with ~10¹¹ M_⊙ baryonic mass. The magnetohydrodynamical simulations are carried out with the PIERNIK code and include star formation, feedback from supernova, and cosmic ray advection and diffusion, on a uniform grid with 195 pc spatial resolution. We find that the introduction of a cold gas stream accreted by the disc enhances galactic star formation. Lower angular momentum streams result in more compact discs, higher star formation rates and stronger outflows. In agreement with previous studies, models including cosmic rays launch stronger outflows travelling much further into the galactic halo. Cosmic ray supported outflows are also cooler than supernova only driven outflows. With cosmic rays, the star formation is suppressed and the thermal pressure is reduced. We find evidence for two distinct outflow phases. The warm outflows have high angular momentum and stay close to the galactic disc, while the hot outflow phase has low angular momentum and escapes from the centre deep into the halo. Cosmic rays can therefore have a strong impact on galaxy evolution by removing low angular momentum, possibly metal enriched gas from the disc and injecting it into the circumgalactic medium.

M 31 has experienced a recent tumultuous merger history, as evidenced from the many substructures that are still present in its inner halo, particularly the G1-Clump, NE-, and W-shelves and the Giant Stream (GS). We present planetary nebulae (PNe) line-of-sight velocity (LOSV) measurements covering the entire spatial extent of these four substructures. We further use predictions for the satellite and host stellar particle phase space distributions for a major merger (mass ratio = 1:4) simulation to help interpret the data. The measured PN LOSVs for the two shelves and GS are consistent with those from red giant branch stars. Their projected radius versus LOSV phase space, links the formation of these substructures in a single unique event, consistent with a major merger. We find the G1-clump to be dynamically cold compared to the M 31 disc ($\rm \sigma _{LOS, PN}=27$ km s^-1), consistent with pre-merger disc material. Such a structure can not form in a minor merger (mass ratio ~1:20) and is therefore a smoking gun for the recent major merger event in M 31. The simulation also predicts the formation of a predominantly in situ halo from splashed-out pre-merger disc material, in qualitative agreement with observations of a metal-rich inner halo in M 31. Juxtaposed with previous results for its discs, we conclude that M 31 has had a recent (2.5-4 Gyr ago) 'wet' major merger with the satellite falling along the GS, heating the pre-merger disc to form the M 31 thicker disc, rebuilding the M 31 thin disc, and creating the aforementioned inner-halo substructures.

We study how light scalar fields can change the stellar landscape by triggering a new phase of nuclear matter. Scalars coupled to nucleons can develop a non-trivial expectation value at finite baryon density. This sourcing of a scalar reduces the nucleon mass and provides an additional energy density and pressure source. Under generic conditions, a new ground state of nuclear matter emerges, with striking implications for the configuration of stellar remnants. Notably, neutron stars in the new ground state can be significantly heavier than QCD equations of state currently predict. We also find hybrid stellar compositions and stable self-bound objects with sizes as small as the Compton wavelength of the scalar. We discuss several specific realizations of this scenario: the QCD axion and lighter generalizations thereof and linearly or quadratically coupled scalar fields effectively equivalent to a class of scalar-tensor modification of gravity. Lastly, we explore phenomenological signatures relevant to electromagnetic and gravitational wave observations of neutron stars, such as atypical compactness and instability gaps in radii.

SMSS J114447.77-430859.3 (z = 0.83) has been identified in the SkyMapper Southern Survey as the most luminous quasar in the last $\sim 9\, \rm Gyr$ . In this paper, we report on the eROSITA/Spectrum-Roentgen-Gamma (SRG) observations of the source from the eROSITA All Sky Survey, along with presenting results from recent monitoring performed using Swift, XMM-Newton, and NuSTAR. The source shows a clear variability by factors of ~10 and ~2.7 over time-scales of a year and of a few days, respectively. When fit with an absorbed power law plus high-energy cutoff, the X-ray spectra reveal a Γ = 2.2 ± 0.2 and $E_{\rm cut}=23^{+26}_{-5}\, \rm keV$ . Assuming Comptonization, we estimate a coronal optical depth and electron temperature of $\tau =2.5-5.3\, (5.2-8)$ and $kT=8-18\, (7.5-14)\, \rm keV$ , respectively, for a slab (spherical) geometry. The broadband SED is successfully modelled by assuming either a standard accretion disc illuminated by a central X-ray source, or a thin disc with a slim disc emissivity profile. The former model results in a black hole mass estimate of the order of $10^{10}\, \mathrm{ M}_\odot$ , slightly higher than prior optical estimates; meanwhile, the latter model suggests a lower mass. Both models suggest sub-Eddington accretion when assuming a spinning black hole, and a compact ($\sim 10\, r_{\rm g}$ ) X-ray corona. The measured intrinsic column density and the Eddington ratio strongly suggest the presence of an outflow driven by radiation pressure. This is also supported by variation of absorption by an order of magnitude over the period of $\sim 900 \ \rm d$ .

A distributed system increases flexibility and enables the reuse of components between different CubeSat missions. Within this thesis, we present a suitable distributed system and evaluate its performance regarding distributed real-time applications with a major focus on time synchronization and timed execution capabilities. Additionally, we evaluate the radiation tolerance of a target microcontroller to assure reliable operation in the South Atlantic Anomaly.

We present EXplosive TRAnsient Spectral Simulator (EXTRASS), a newly developed code aimed at generating 3D spectra for supernovae in the nebular phase by using modern multidimensional explosion models as input. It is well established that supernovae are asymmetric by nature, and that the morphology is encoded in the line profiles during the nebular phase, months after the explosion. In this work, we use EXTRASS to study one such simulation of a $3.3\, \mathrm{ M}_\odot$ He-core explosion ($M_\text{ejecta}=1.3\, M_\odot$, $E_\text{kin}=1.05\times 10^{51}\,$erg) modelled with the Prometheus-HotB code and evolved to the homologous phase. Our code calculates the energy deposition from the radioactive decay of ⁵⁶Ni → ⁵⁶Co → ⁵⁶Fe and uses this to determine the Non-Local-Thermodynamic-Equilibrium temperature, excitation, and ionization structure across the nebula. From the physical condition solutions we generate the emissivities to construct spectra depending on viewing angles. Our results show large variations in the line profiles with viewing angles, as diagnosed by the first three moments of the line profiles; shifts, widths, and skewness. We compare line profiles from different elements, and study the morphology of line-of-sight slices that determine the flux at each part of a line profile. We find that excitation conditions can sometimes make the momentum vector of the ejecta emitting in the excited states significantly different from that of the bulk of the ejecta of the respective element, thus giving blueshifted lines for bulk receding material, and vice versa. We compare the 3.3 M_⊙ He-core model to observations of the Type Ib supernova SN 2007Y.

The distribution of baryons provides a significant way to understand the formation of galaxy clusters by revealing the details of its internal structure and changes over time. In this paper, we present theoretical studies on the scaled profiles of physical properties associated with the baryonic components, including gas density, temperature, metallicity, pressure and entropy as well as stellar mass, metallicity and satellite galaxy number density in galaxy clusters from z = 4 to z = 0 by tracking their progenitors. These mass-complete simulated galaxy clusters are coming from THE THREE HUNDRED with two runs: GIZMO-SIMBA and GADGET-X. Through comparisons between the two simulations, and with observed profiles that are generally available at low redshift, we find that (1) the agreements between the two runs and observations are mostly at outer radii r ≳ 0.3r₅₀₀, in line with the self-similarity assumption. While GADGET-X shows better agreements with the observed gas profiles in the central regions compared to GIZMO-SIMBA; (2) the evolution trends are generally consistent between the two simulations with slightly better consistency at outer radii. In detail, the gas density profile shows less discrepancy than the temperature and entropy profiles at high redshift. The differences in the cluster centre and gas properties imply different behaviours of the AGN models between GADGET-X and GIZMO-SIMBA, with the latter, maybe too strong for this cluster simulation. The high-redshift difference may be caused by the star formation and feedback models or hydrodynamics treatment, which requires observation constraints and understanding.

While hot ICM in galaxy clusters makes these objects powerful X-ray sources, the cluster's outskirts and overdense gaseous filaments might give rise to much fainter sub-keV emission. Cosmological simulations show a prominent 'focusing' effect of rich clusters on the space density of the warm-hot intergalactic medium (WHIM) filaments up to a distance of $\sim 10\, {\rm Mpc}$ (~ turnaround radius, r_ta) and beyond. Here, we use Magneticum simulations to characterize their properties in terms of integrated emission measure for a given temperature and overdensity cut and the level of contamination by the more dense gas. We suggest that the annuli $(\sim 0.5-1)\times \, r_{ta}$ around massive clusters might be the most promising sites for the search of the gas with overdensity ≲ 50. We model spectral signatures of the WHIM in the X-ray band and identify two distinct regimes for the gas at temperatures below and above $\sim 10^6\, {\rm K}$. Using this model, we estimate the sensitivity of X-ray telescopes to the WHIM spectral signatures. We found that the WHIM structures are within reach of future high spectral resolution missions, provided that the low-density gas is not extremely metal-poor. We then consider the Coma cluster observed by SRG/eROSITA during the CalPV phase as an example of a nearby massive object. We found that beyond the central r ~ 40 arcmin ($\sim 1100\, {\rm kpc}$) circle, where calibration uncertainties preclude clean separation of the extremely bright cluster emission from a possible softer component, the conservative upper limits are about an order of magnitude larger than the levels expected from simulations.

We develop a model to reproduce the mass distributions of pairs of mesons in the Cabibbo-suppressed $D^+_s \to K^+ \pi^+ \pi^-$ decay. The largest contributions to the process comes from the $D^+_s \to K^+ \rho^0$ and $D^+_s \to K^{*0} \pi^+$ decay modes, but the $D^+_s \to K^*_0(1430) \pi^+$ and $D^+_s \to K^+ f_0(1370)$ modes also play a moderate role and all of them are introduced empirically. Instead, the contribution of the $f_0(500)$, $f_0(980)$ and $K^*_0(700)$ resonances is introduced dynamically by looking at the decay modes at the quark level, hadronizing $q \bar{q}$ pairs to give two mesons, and allowing these mesons to interact to finally produce the $K^+ \pi^+ \pi^-$ final state. These last three modes are correlated by means of only one parameter. We obtain a fair reproduction of the experimental data for the three mass distributions as well as the relative weight of the three light scalar mesons, which we see as further support for the nature of these states as dynamically generated from the interaction of pseudoscalar mesons.

We investigate the coalescence of massive black hole ($M_{\rm BH}\gtrsim 10^{6}~\rm {\rm M}_{\odot }$) binaries (MBHBs) at 6 < z < 10 by adopting a suite of cosmological hydrodynamical simulations of galaxy formation, zoomed-in on biased (>3σ) overdense regions (M_h ~ 10¹² M_⊙ dark matter haloes at z = 6) of the Universe. We first analyse the impact of different resolutions and AGN feedback prescriptions on the merger rate, assuming instantaneous mergers. Then, we compute the halo bias correction factor due to the overdense simulated region. Our simulations predict merger rates that range between 3 and 15 $\rm yr^{-1}$ at z ~6, depending on the run considered, and after correcting for a bias factor of ~20-30. For our fiducial model, we further consider the effect of delay in the MBHB coalescence due to dynamical friction. We find that 83 per cent of MBHBs will merge within the Hubble time, and 21 per cent within 1 Gyr, namely the age of the Universe at z > 6. We finally compute the expected properties of the gravitational wave (GW) signals and find the fraction of LISA detectable events with high signal-to-noise ratio (SNR > 5) to range between 66 per cent and 69 per cent. However, identifying the electro-magnetic counterpart of these events remains challenging due to the poor LISA sky localization that, for the loudest signals ($\mathcal {M}_c\sim 10^6~{{\rm M}_{\odot }}$ at z = 6), is around 10 $\rm deg^2$.

In the context of a project aimed at characterizing the properties of the so-called Bulge Fossil Fragments (the fossil remnants of the bulge formation epoch), here we present the first determination of the metallicity distribution of Liller 1. For a sample of 64 individual member stars we used ESO-MUSE spectra to measure the equivalent width of the Ca II triplet and then derive the iron abundance. To test the validity of the adopted calibration in the metal-rich regime, the procedure was first applied to three reference bulge globular clusters (NGC 6569, NGC 6440, and NGC 6528). In all the three cases, we found single-component iron distributions, with abundance values fully in agreement with those reported in the literature. The application of the same methodology to Liller 1 yielded, instead, a clear bimodal iron distribution, with a subsolar component at [Fe/H] = -0.48 dex (σ = 0.22) and a supersolar component at [Fe/H] = +0.26 dex (σ = 0.17). The latter is found to be significantly more centrally concentrated than the metal-poor population, as expected in a self-enrichment scenario and in agreement with that found in another bulge system, Terzan 5. The obtained metallicity distribution is astonishingly similar to that predicted by the reconstructed star formation history of Liller 1, which is characterized by three main bursts and a low, but constant, activity of star formation over the entire lifetime. These findings provide further support to the possibility that, similar to Terzan 5, Liller 1 is also a Bulge Fossil Fragment. ^* Based on observations collected at the Very Large Telescope of the European Southern Observatory, Cerro Paranal (Chile), under the ESO-VLT Multi-Instrument Kinematic Survey (MIKiS survey) programs 106.21N5 and 105.20B9 (PI: Ferraro) and under MUSE science verification programs: 60.A-9489;60.A-9343.

Time-delay distance measurements of strongly lensed quasars have provided a powerful and independent probe of the current expansion rate of the Universe (H₀). However, in light of the discrepancies between early- and late-time cosmological studies, current efforts revolve around the characterisation of systematic uncertainties in the methods. In this work we focus on the mass-sheet degeneracy (MSD), which is commonly considered a significant source of systematics in time-delay strong lensing studies, and aim to assess the constraining power provided by integral field unit (IFU) stellar kinematics. To this end, we approximated the MSD with a cored, two-parameter extension to the adopted lensing mass profiles (with core radius r_c and mass-sheet parameter λ_int), which introduces a full degeneracy between λ_int and H₀ from lensing data alone. In addition, we utilised spatially resolved mock IFU stellar kinematics of time-delay strong lenses, given the prospects of obtaining such high-quality data with the James Webb Space Telescope (JWST) in the near future. We constructed joint strong lensing and generalised two-integral axisymmetric Jeans models, where the time delays, mock imaging, and IFU observations are used as input to constrain the mass profile of lens galaxies at the individual galaxy level and consequently yield joint constraints on the time-delay distance (D_Δt) and the angular diameter distance (D_d) to the lens. We find that mock JWST-like stellar kinematics constrain the amount of internal mass sheet that is physically associated with the lens galaxy and limit its contribution to the uncertainties of D_Δt and D_d, each at the ≤4% level, without assumptions on the background cosmological model. Incorporating additional uncertainties due to external mass sheets associated with mass structures along the lens line of sight, these distance constraints would translate to a ≲4% precision measurement on H₀ in flat Λ cold dark matter cosmology for a single lens. Our study shows that future IFU stellar kinematics of time-delay lenses will be key in lifting the MSD on a per lens basis, assuming reasonable and physically motivated core sizes. However, even in the limit of infinite r_c, where D_Δt is fully degenerate with λ_int and is thus not constrained, stellar kinematics of the deflector, time delays, and imaging data will provide powerful constraints on D_d, which becomes the dominant source of information in the cosmological inference.

We apply the cobordism hypothesis with singularities to the case of affine Rozansky--Witten models, providing a construction of extended TQFTs that includes all line and surface defects. On a technical level, this amounts to proving that the associated homotopy 2-category is pivotal, and to systematically employing its 3-dimensional graphical calculus. This in particular allows us to explicitly calculate state spaces for surfaces with arbitrary defect networks. As specific examples we discuss symmetry defects which can be used to model non-trivial background gauge fields, as well as boundary conditions.

We study the decay J /ψ →π⁺π^-π⁰ within the framework of the Khuri-Treiman equations. We find that the BESIII experimental dipion mass distribution in the ρ (770 )-region is well reproduced with a once-subtracted P -wave amplitude. Furthermore, we show that F -wave contributions to the amplitude improve the description of the data in the π π mass region around 1.5 GeV. We also present predictions for the J /ψ →π⁰γ^* transition form factor.

The building of planetary systems is controlled by the gas and dust dynamics of protoplanetary disks. While the gas is simultaneously accreted onto the central star and dissipated away by winds, dust grains aggregate and collapse to form planetesimals and eventually planets. This dust and gas dynamics involves instabilities, turbulence and complex non-linear interactions which ultimately control the observational appearance and the secular evolution of these disks. This chapter is dedicated to the most recent developments in our understanding of the dynamics of gaseous and dusty disks, covering hydrodynamic and magnetohydrodynamic turbulence, gas-dust instabilities, dust clumping and disk winds. We show how these physical processes have been tested from observations and highlight standing questions that should be addressed in the future.

The field of planet formation is in an exciting era, where recent observations of disks around low- to intermediate-mass stars made with state of the art interferometers and high-contrast optical and IR facilities have revealed a diversity of substructures, some possibly planet-related. It is therefore important to understand the physical and chemical nature of the protoplanetary building blocks, as well as their spatial distribution, to better understand planet formation. Since PPVI, the field has seen tremendous improvements in observational capabilities, enabling both surveys of large samples of disks and high resolution imaging studies of a few bright disks. Improvements in data quality and sample size have, however, opened up many fundamental questions about properties such as the mass budget of disks, its spatial distribution, and its radial extent. Moreover, the vertical structure of disks has been studied in greater detail with spatially resolved observations, providing new insights on vertical layering and temperature stratification, yet also bringing rise to questions about other properties, such as material transport and viscosity. Each one of these properties—disk mass, surface density distribution, outer radius, vertical extent, temperature structure, and transport—is of fundamental interest as they collectively set the stage for disk evolution and corresponding planet formation theories. In this chapter, we will review our understanding of the fundamental properties of disks including the relevant observational techniques to probe their nature, modeling methods, and the respective caveats. Finally, we discuss the implications for theories of disk evolution and planet formation underlining what new questions have since arisen as our observational facilities have improved.

In order to predict the cosmological abundance of dark matter, an estimation of particle rates in an expanding thermal environment is needed. For thermal dark matter, the non-relativistic regime sets the stage for the freeze-out of the dark matter energy density. We compute transition widths and annihilation, bound-state formation, and dissociation cross sections of dark matter fermion pairs in the unifying framework of non-relativistic effective field theories at finite temperature, with the thermal bath modeling the thermodynamical behaviour of the early universe. We reproduce and extend some known results for the paradigmatic case of a dark fermion species coupled to dark gauge bosons. The effective field theory framework allows to highlight their range of validity and consistency, and to identify some possible improvements.

In this manuscript, we elaborate on a procedure to derive ϵ-factorised differential equations for multi-scale, multi-loop classes of Feynman integrals that evaluate to special functions beyond multiple polylogarithms. We demonstrate the applicability of our approach to diverse classes of problems, by working out ϵ-factorised differential equations for single- and multi-scale problems of increasing complexity. To start we are reconsidering the well-studied equal-mass two-loop sunrise case, and move then to study other elliptic two-, three- and four-point problems depending on multiple different scales. Finally, we showcase how the same approach allows us to obtain ϵ-factorised differential equations also for Feynman integrals that involve geometries beyond a single elliptic curve.

We consider electrically neutral complex-vector particles V below the GeV mass scale that, from a low-energy perspective, couple to the photon via higher-dimensional form factor interactions. We derive ensuing astrophysical constraints by considering the anomalous energy loss from the Sun, Horizontal Branch, and Red Giant stars as well as from SN1987A that arise from vector pair production in these environments. Under the assumption that the dark states V constitute dark matter, the bounds are then complemented by direct and indirect detection as well as cosmological limits. The relic density from freeze-out and freeze-in mechanisms is also computed. On the basis of a UV-complete model that realizes the considered effective couplings, we also discuss the naturalness of the constrained parameter space, and provide an analysis of the zero mass limit of V .

We study a neural network framework for the numerical evaluation of Feynman loop integrals that are fundamental building blocks for perturbative computations of physical observables in gauge and gravity theories. We show that such a machine learning approach improves the convergence of the Monte Carlo algorithm for high-precision evaluation of multi-dimensional integrals compared to traditional algorithms. In particular, we use a neural network to improve the importance sampling. For a set of representative integrals appearing in the computation of the conservative dynamics for a compact binary system in General Relativity, we perform a quantitative comparison between the Monte Carlo integrators VEGAS and i-flow, an integrator based on neural network sampling.

We demonstrate the importance of quantum jumps in the nonequilibrium evolution of bottomonium states in the quark-gluon plasma. Based on nonrelativistic effective field theory and the open quantum system framework, we evolve the density matrix of color singlet and octet pairs. We show that quantum regeneration of singlet states from octet configurations is necessary to understand experimental results for the suppression of both bottomonium ground and excited states. The values of the heavy-quarkonium transport coefficients used are consistent with recent lattice QCD determinations.

Galaxy clusters in the Universe occupy the important position of nodes of the cosmic web. They are connected among them by filaments, elongated structures composed of dark matter, galaxies, and gas. The connection of galaxy clusters to filaments is important, as it is related to the process of matter accretion onto the former. For this reason, investigating the connections to the cosmic web of massive clusters, especially well-known ones for which a lot of information is available, is a hot topic in astrophysics. In a previous work, we performed an analysis of the filament connections of the Coma cluster of galaxies, as detected from the observed galaxy distribution. In this work we resort to a numerical simulation whose initial conditions are constrained to reproduce the local Universe, including the region of the Coma cluster to interpret our observations in an evolutionary context. We detect the filaments connected to the simulated Coma cluster and perform an accurate comparison with the cosmic web configuration we detect in observations. We perform an analysis of the halos' spatial and velocity distributions close to the filaments in the cluster outskirts. We conclude that, although not significantly larger than the average, the flux of accreting matter on the simulated Coma cluster is significantly more collimated close to the filaments with respect to the general isotropic accretion flux. This paper is the first example of such a result and the first installment in a series of publications which will explore the build-up of the Coma cluster system in connection to the filaments of the cosmic web as a function of redshift.

Galaxy evolution is an important topic, and our physical understanding must be complete to establish a correct picture. This includes a thorough treatment of feedback. The effects of thermal–mechanical and radiative feedback have been widely considered; however, cosmic rays (CRs) are also powerful energy carriers in galactic ecosystems. Resolving the capability of CRs to operate as a feedback agent is therefore essential to advance our understanding of the processes regulating galaxies. The effects of CRs are yet to be fully understood, and their complex multi-channel feedback mechanisms operating across the hierarchy of galaxy structures pose a significant technical challenge. This review examines the role of CRs in galaxies, from the scale of molecular clouds to the circumgalactic medium. An overview of their interaction processes, their implications for galaxy evolution, and their observable signatures is provided and their capability to modify the thermal and hydrodynamic configuration of galactic ecosystems is discussed. We present recent advancements in our understanding of CR processes and interpretation of their signatures, and highlight where technical challenges and unresolved questions persist. We discuss how these may be addressed with upcoming opportunities.

Context. Galaxy clusters are the most massive bound objects in the recent history of the universe; the number density of galaxy clusters as a function of mass and redshift is a sensitive function of the cosmological parameters. To use clusters for cosmological parameter studies, it is necessary to determine their masses as accurately as possible, which is typically done via scaling relations between mass and observables.
Aims: X-ray observables can be biased by a number of effects, including multiphase gas and projection effects, especially in the case where cluster temperatures and luminosities are estimated from single-model fits to all of the emission with an overdensity radius such as r_500c. Using simulated galaxy clusters from a realistic cosmological simulation, our aim is to determine the importance of these biases in the context of Spectrum-Roentgen-Gamma/eROSITA observations of clusters.
Methods: We extracted clusters from the Box2_hr simulation from the Magneticum suite, and simulated synthetic eROSITA observations of these clusters using PHOX to generate the photons and the end-to-end simulator SIXTE to trace them through the optics and simulate the detection process. We fitted the spectra from these observations and compared the fitted temperatures and luminosities to the quantities derived from the simulations. We fitted an intrinsically scattered L_X − T scaling relation to these measurements following a Bayesian approach with which we fully took into account the selection effects and the mass function.
Results: The largest biases on the estimated temperature and luminosities of the clusters come from the inadequacy of single-temperature model fits to represent emission from multiphase gas, and from a bias arising from cluster emission within the projected r_500c along the line of sight but outside of the spherical r_500c. We find that the biases on temperature and luminosity due to the projection of emission from other clusters within r_500c is comparatively small. We find eROSITA-like measurements of Magneticum clusters following a L_X − T scaling relation that has a broadly consistent but slightly shallower slope compared to the literature values. We also find that the intrinsic scatter of L_X at given T is lower compared to the recent observational results where the selection effects are fully considered.

Context. Observational studies carried out to calibrate the masses of galaxy clusters often use mass-richness relations to interpret galaxy number counts.
Aims: Here, we aim to study the impact of the richness-mass relation modelled with cosmological parameters on mock mass calibrations.
Methods: We build a Gaussian process regression emulator of high-mass satellite abundance normalisation and log-slope based on cosmological parameters Ω_m, Ω_b, σ₈, h₀, and redshift z. We train our emulator using Magneticum hydrodynamic simulations that span different cosmologies for a given set of feedback scheme parameters.
Results: We find that the normalisation depends, albeit weakly, on cosmological parameters, especially on Ω_m and Ω_b, and that their inclusion in mock observations increases the constraining power of these latter by 10%. On the other hand, the log-slope is ≈1 in every setup, and the emulator does not predict it with significant accuracy. We also show that satellite abundance cosmology dependency differs between full-physics simulations, dark-matter only, and non-radiative simulations.
Conclusions: Mass-calibration studies would benefit from modelling of the mass-richness relations with cosmological parameters, especially if the satellite abundance cosmology dependency.

We investigate the nucleosynthesis and kilonova properties of binary neutron star (NS) merger models that lead to intermediate remnant lifetimes of ~0.1-1 s until black hole (BH) formation and describe all components of the material ejected during the dynamical merger phase, NS remnant evolution, and final viscous disintegration of the BH torus after gravitational collapse. To this end, we employ a combination of hydrodynamics, nucleosynthesis, and radiative transfer tools to achieve a consistent end-to-end modeling of the system and its observables. We adopt a novel version of the Shakura-Sunyaev scheme allowing the approximate turbulent viscosity inside the NS remnant to vary independently of the surrounding disk. We find that asymmetric progenitors lead to shorter remnant lifetimes and enhanced ejecta masses, although the viscosity affects the absolute values of these characteristics. The integrated production of lanthanides and heavier elements in such binary systems is subsolar, suggesting that the considered scenarios contribute in a subdominant fashion to r-process enrichment. One reason is that BH tori formed after delayed collapse exhibit less neutron-rich conditions than typically found, and often assumed in previous BH torus models, for early BH formation. The outflows in our models feature strong anisotropy as a result of the lanthanide-poor polar neutrino-driven wind pushing aside lanthanide-rich dynamical ejecta. Considering the complexity of the models, the estimated kilonova light curves show promising agreement with AT 2017gfo after times of several days, while the remaining inconsistencies at early times could possibly be overcome in binary configurations with a more dominant neutrino-driven wind relative to the dynamical ejecta.

Majoron-like bosons would emerge from a supernova (SN) core by neutrino coalescence of the form ν ν →ϕ and ν ¯ν ¯→ϕ with 100-MeV-range energies. Subsequent decays to (anti)neutrinos of all flavors provide a flux component with energies much larger than the usual flux from the "neutrino sphere." The absence of 100-MeV-range events in the Kamiokande-II and Irvine-Michigan-Brookhaven signal of SN 1987A implies that less than 1% of the total energy was thus emitted and provides the strongest constraint on the Majoron-neutrino coupling of g ≲10^-9 MeV /m_ϕ for 100 eV ≲m_ϕ≲100 MeV . It is straightforward to extend our new argument to other hypothetical feebly interacting particles.

We discuss the recent progress that has been made towards the computation of three-loop non-planar master integrals relevant to next-to-next-to-next-to-leading-order (N$^3$LO) corrections to processes such as H+jet production at the LHC. We describe the analytic structure of these integrals, as well as several technical issues regarding their analytic computation using canonical differential equations. Finally, we comment on the remaining steps towards the computation of all relevant three-loop topologies and their application to amplitude calculations.

The effective field theory of large-scale structure allows for a consistent perturbative bias expansion of the rest-frame galaxy density field. In this work, we present a systematic approach to renormalize galaxy bias and stochastic parameters using a finite cutoff scale $\Lambda$. We derive the differential equations of the Wilson-Polchinski renormalization group that describe the evolution of the finite-scale bias parameters with $\Lambda$, analogous to the $\beta$-function running in QFT. We further provide the connection between the finite-cutoff scheme and the renormalization procedure for $n$-point functions that has been used as standard in the literature so far; some inconsistencies in the treatment of renormalized bias in current EFT analyses are pointed out as well. The fixed-cutoff scheme allows us to predict, in a principled way, the finite part of loop contributions which is due to perturbative modes and which, in the standard renormalization approach, is absorbed into counterterms. We expect that this will allow for the robust extraction of (a yet-to-be-determined amount of) additional cosmological information from galaxy clustering, both when using field-level techniques and $n$-point functions.

New-generation direct searches for low mass dark matter feature detection thresholds at energies well below 100 eV, much lower than the energies of commonly used x-ray calibration sources. This requires new calibration sources with sub-keV energies. When searching for nuclear recoil signals, the calibration source should ideally cause monoenergetic nuclear recoils in the relevant energy range. Recently, a new calibration method based on the radiative neutron capture on ¹⁸²W with subsequent deexcitation via single γ -emission leading to a nuclear recoil peak at 112 eV was proposed. The CRESST-III dark matter search operated several CaWO₄-based detector modules with detection thresholds below 100 eV in the past years. We report the observation of a peak around the expected energy of 112 eV in the data of three different detector modules recorded while irradiated with neutrons from different AmBe calibration sources. We compare the properties of the observed peaks with GEANT-4 simulations and assess the prospects of using this for the energy calibration of CRESST-III detectors.

The task of reconstructing particles from low-level detector response data to predict the set of final state particles in collision events represents a set-to-set prediction task requiring the use of multiple features and their correlations in the input data. We deploy three separate set-to-set neural network architectures to reconstruct particles in events containing a single jet in a fully-simulated calorimeter. Performance is evaluated in terms of particle reconstruction quality, properties regression, and jet-level metrics. The results demonstrate that such a high-dimensional end-to-end approach succeeds in surpassing basic parametric approaches in disentangling individual neutral particles inside of jets and optimizing the use of complementary detector information. In particular, the performance comparison favors a novel architecture based on learning hypergraph structure, HGPflow, which benefits from a physically-interpretable approach to particle reconstruction.

The singlet sector of the O(N) ϕ⁴-model in AdS₄ at large-N, gives rise to a dual conformal field theory on the conformal boundary of AdS₄, which is a deformation of the generalized free field. We identify and compute an AdS₄ three-point one-loop fish diagram that controls the exact large-N dimensions and operator product coefficients (OPE) for all "double trace" operators as a function of the renormalized ϕ⁴-couplings. We find that the space of ϕ⁴-coupling is compact with a boundary at the bulk Landau pole. The dual CFT is unitary only in an interval of negative couplings bounded by the Landau pole where the lowest OPE coefficient diverges.

A modular representation for the semileptonic decays of baryons originating from spin-polarized and correlated baryon-antibaryon pairs is derived. The complete spin information of the decaying baryon is propagated to the daughter baryon via a real-valued matrix. It allows us to obtain joint differential distributions in sequential processes involving the semileptonic decay in a straightforward way. The formalism is suitable for extraction of the semileptonic form factors in experiments where strange baryon-antibaryon pairs are produced in electron-positron annihilation or in charmonia decays. We give examples such as the complete angular distributions in the e⁺e^-→Λ Λ ¯ process, where Λ →p e^-ν_¯e and Λ ¯→p ¯π⁺. The formalism can also be used to describe the distributions in semileptonic decays of charm and bottom baryons. Using the same principles, the modules to describe electromagnetic and neutral current weak baryon decay processes involving a charged lepton-antilepton pair can be obtained. As an example, we provide the decay matrix for the Dalitz transition between two spin-1 /2 baryons.

We study the relation between the metallicities of ionized and atomic gas in star-forming galaxies at z = 0-3 using the Evolution and Assembly of GaLaxies and their Environments (EAGLE) cosmological, hydrodynamical simulations. This is done by constructing a dense grid of sight lines through the simulated galaxies and obtaining the star formation rate- and H I column density-weighted metallicities, Z _SFR and Z _{H I}, for each sightline as proxies for the metallicities of ionized and atomic gas, respectively. We find Z _SFR ≳ Z _{H I} for almost all sight lines, with their difference generally increasing with decreasing metallicity. The stellar masses of galaxies do not have a significant effect on this trend, but the positions of the sight lines with respect to the galaxy centers play an important role: the difference between the two metallicities decreases when moving toward the galaxy centers, and saturates to a minimum value in the central regions of galaxies, irrespective of redshift and stellar mass. This implies that the mixing of the two gas phases is most efficient in the central regions of galaxies where sight lines generally have high column densities of H I. However, a high H I column density alone does not guarantee a small difference between the two metallicities. In galaxy outskirts, the inefficiency of the mixing of star-forming gas with H I seems to dominate over the dilution of heavy elements in H I through mixing with the pristine gas. We find good agreement between the available observational data and the Z _SFR-Z _{H I} relation predicted by the EAGLE simulations. Though, observed regions with a nuclear starburst mode of star formation appear not to follow the same relation.

Intracellular protein patterns regulate a variety of vital cellular processes such as cell division and motility, which often involve dynamic cell-shape changes. These changes in cell shape may in turn affect the dynamics of pattern-forming proteins, hence leading to an intricate feedback loop between cell shape and chemical dynamics. While several computational studies have examined the rich resulting dynamics, the underlying mechanisms are not yet fully understood. To elucidate some of these mechanisms, we explore a conceptual model for cell polarity on a dynamic one-dimensional manifold. Using concepts from differential geometry, we derive the equations governing mass-conserving reaction-diffusion systems on time-evolving manifolds. Analyzing these equations mathematically, we show that dynamic shape changes of the membrane can induce pattern-forming instabilities in parts of the membrane, which we refer to as regional instabilities. Deformations of the local membrane geometry can also (regionally) suppress pattern formation and spatially shift already existing patterns. We explain our findings by applying and generalizing the local equilibria theory of mass-conserving reaction-diffusion systems. This allows us to determine a simple onset criterion for geometry-induced pattern-forming instabilities, which is linked to the phase-space structure of the reaction-diffusion system. The feedback loop between membrane shape deformations and reaction-diffusion dynamics then leads to a surprisingly rich phenomenology of patterns, including oscillations, traveling waves, and standing waves, even if these patterns do not occur in systems with a fixed membrane shape. Our paper reveals that the local conformation of the membrane geometry acts as an important dynamical control parameter for pattern formation in mass-conserving reaction-diffusion systems.

It may be unsurprising that the most common approach to finding proto-clusters is to search for over-densities of galaxies. Upgrades to submillimetre (submm) interferometers and the advent of the James Webb Space Telescope will soon offer the opportunity to find more distant candidate proto-clusters in deep sky surveys without any spectroscopic confirmation. In this Letter, we report the serendipitous discovery of an extremely dense region centred on the blazar, J0217−0820, at z = 0.6 in the ALMACAL sky survey. Its density is eight times higher than that predicted by blind submm surveys. Among the seven submm-bright galaxies, three are as bright as conventional single-dish submm galaxies, with S_{870 μm} > 3 mJy. The over-density is thus comparable to the densest known and confirmed proto-cluster cores. However, their spectra betray a wide range of redshifts. We investigate the likelihood of line-of-sight projection effects using light cones from cosmological simulations, finding that the deeper we search, the higher the chance that we will suffer from such projection effects. The extreme over-density around J0217−0820 demonstrates the strong cosmic variance we may encounter in the deep submm surveys. Thus, we should also question the fidelity of galaxy proto-cluster candidates selected via over-densities of galaxies, where the negative K correction eases the detection of dusty galaxies along an extraordinarily extended line of sight.

We analyse the full shape of anisotropic clustering measurements from the extended Baryon Oscillation Spectroscopic Survey quasar sample together with the combined galaxy sample from the Baryon Oscillation Spectroscopic Survey. We obtain constraints on the cosmological parameters independent of the Hubble parameter h for the extensions of the Lambda cold dark matter (ΛCDM) models, focusing on cosmologies with free dark energy equation of state parameter w. We combine the clustering constraints with those from the latest cosmic microwave background data from Planck to obtain joint constraints for these cosmologies for w and the additional extension parameters - its time evolution w_a, the physical curvature density ω_K and the neutrino mass sum ∑m_ν. Our joint constraints are consistent with a flat ΛCDM cosmological model within 68 per cent confidence limits. We demonstrate that the Planck data are able to place tight constraints on the clustering amplitude today, σ₁₂, in cosmologies with varying w and present the first constraints for the clustering amplitude for such cosmologies, which is found to be slightly higher than the ΛCDM value. Additionally, we show that when we vary w and allow for non-flat cosmologies and the physical curvature density is used, Planck prefers a curved universe at 4σ significance, which is ~2σ higher than when using the relative curvature density Ω_K. Finally, when w is varied freely, clustering provides only a modest improvement (of 0.021 eV) on the upper limit of ∑m_ν.

I describe the history of the calculations of NLO and NNLO QCD corrections to weak decays of mesons, particle-antiparticle mixing and electric dipole moments (EDMs) in the period 1988-2023. Also existing calculations of electroweak and QED corrections to these processes are included in this presentation. These efforts bear some analogies to the climbing of Himalayas and various expeditions by several teams of strongly motivated "climbers" allowed to move this field from the LO through the NLO to the NNLO level. We also summarize the most recent calculations within the Standard Model Effective Field Theory. The material is meant to be an up to date review of this very advanced field in non-technical terms as much as possible and a guide to the rich literature on NLO and NNLO corrections in question. In particular we stress for which processes these calculations are crucial for the tests of the Standard Model and to be able to differentiate between numerous New Physics models. It includes also several anecdotes related to the climbs that I was involved in. I hope that some of the comments made in the course of the presentation could turn out to be not only amusing but also instructive.

We cross-correlate positions of galaxies measured in data from the first three years of the Dark Energy Survey with Compton-y maps generated using data from the South Pole Telescope (SPT) and the Planck mission. We model this cross-correlation measurement together with the galaxy autocorrelation to constrain the distribution of gas in the Universe. We measure the hydrostatic mass bias or, equivalently, the mean halo bias-weighted electron pressure <b_hP_e >, using large-scale information. We find <b_hP_e > to be $[0.16^{+0.03}_{-0.04},0.28^{+0.04}_{-0.05},0.45^{+0.06}_{-0.10},0.54^{+0.08}_{-0.07},0.61^{+0.08}_{-0.06},0.63^{+0.07}_{-0.08}]$ meV cm^-3 at redshifts z ~ [0.30, 0.46, 0.62, 0.77, 0.89, 0.97]. These values are consistent with previous work where measurements exist in the redshift range. We also constrain the mean gas profile using small-scale information, enabled by the high-resolution of the SPT data. We compare our measurements to different parametrized profiles based on the cosmo-OWLS hydrodynamical simulations. We find that our data are consistent with the simulation that assumes an AGN heating temperature of 10^8.5 K but are incompatible with the model that assumes an AGN heating temperature of 10^8.0 K. These comparisons indicate that the data prefer a higher value of electron pressure than the simulations within r_500c of the galaxies' haloes.

Using numerical simulations, we investigate the gravitational evolution of filamentary molecular cloud structures and their condensation into dense protostellar cores. One possible process is the so-called edge effect, the pile-up of matter at the end of the filament due to self-gravity. This effect is predicted by theory but only rarely observed. To get a better understanding of the underlying processes we used a simple analytic approach to describe the collapse and the corresponding collapse time. We identify a model of two distinct phases. The first phase is free fall dominated, due to the self-gravity of the filament. In the second phase, after the turning point, the collapse is balanced by the ram pressure, produced by the inside material of the filament, which leads to a constant collapse velocity. This approach reproduces the established collapse time of uniform density filaments and agrees well with our hydrodynamic simulations. In addition, we investigate the influence of different radial density profiles on the collapse. We find that the deviations compared to the uniform filament are less than 10 per cent. Therefore, the analytic collapse model of the uniform density filament is an excellent general approach.

In the electroweak sector of the Standard Model, CP violation arises through a very particular interplay between the three quark generations, as described by the Cabibbo-Kobayashi-Maskawa (CKM) mechanism and the single Jarlskog invariant J₄. Once generalized to the Standard Model Effective Field Theory (SMEFT), this peculiar pattern gets modified by higher-dimensional operators, whose associated Wilson coefficients are usually split into CP-even and odd parts. However, CP violation at dimension four, i.e., at the lowest order in the EFT expansion, blurs this distinction: any Wilson coefficient can interfere with J₄ and mediate CP violation. In this paper, we study such interferences at first order in the SMEFT expansion,

We present new GRIFFIN project hydrodynamical simulations that model the formation of galactic star cluster populations in low-metallicity (Z = 0.00021) dwarf galaxies, including radiation, supernova, and stellar wind feedback of individual massive stars. In the simulations, stars are sampled from the stellar initial mass function (IMF) down to the hydrogen-burning limit of 0.08 M_⊙. Mass conservation is enforced within a radius of 1 pc for the formation of massive stars. We find that massive stars are preferentially found in star clusters and follow a correlation set at birth between the highest initial stellar mass and the star cluster mass that differs from pure stochastic IMF sampling. With a fully sampled IMF, star clusters lose mass in the galactic tidal field according to mass-loss rates observed in nearby galaxies. Of the released stellar feedback, 60 per cent of the supernova material and up to 35 per cent of the wind material reside either in the hot interstellar medium (ISM) or in gaseous, metal-enriched outflows. While stellar winds (instantaneously) and supernovae (delayed) start enriching the ISM right after the first massive stars form, the formation of supernova-enriched stars and star clusters is significantly delayed (by >50 Myr) compared to the formation of stars and star clusters enriched by stellar winds. Overall, supernova ejecta dominate the enrichment by mass, while the number of enriched stars is determined by continuous stellar winds. These results present a concept for the formation of chemically distinct populations of stars in bound star clusters, reminiscent of multiple populations in globular clusters.

The current standard cosmological model is constructed within the framework of general relativity with a cosmological constant Λ, which is often associated with dark energy, and phenomenologically explains the accelerated cosmic expansion. Understanding the nature of dark energy is one of the most appealing questions in achieving a self-consistent physical model at cosmological scales. Modification of general relativity could potentially provide a more natural and physical solution to the accelerated expansion. The growth of the cosmic structure is sensitive in constraining gravity models. In this paper, we aim to provide a concise introductory review of modified gravity models from an observational point of view. We will discuss various mainstream cosmological observables, and their potential advantages and limitations as probes of gravity models.

We present magnetohydrodynamic (MHD) simulations of the star-forming multiphase interstellar medium (ISM) in stratified galactic patches with gas surface densities Σ_gas = 10, 30, 50, and 100 $\mathrm{M_\odot \, pc^{-2}}$. The SILCC project simulation framework accounts for non-equilibrium thermal and chemical processes in the warm and cold ISM. The sink-based star formation and feedback model includes stellar winds, hydrogen-ionizing UV radiation, core-collapse supernovae, and cosmic ray (CR) injection and diffusion. The simulations follow the observed relation between Σ_gas and the star formation rate surface density Σ_SFR. CRs qualitatively change the outflow phase structure. Without CRs, the outflows transition from a two-phase (warm and hot at 1 kpc) to a single-phase (hot at 2 kpc) structure. With CRs, the outflow always has three phases (cold, warm, and hot), dominated in mass by the warm phase. The impact of CRs on mass loading decreases for higher Σ_gas and the mass loading factors of the CR-supported outflows are of order unity independent of Σ_SFR. Similar to observations, vertical velocity dispersions of the warm ionized medium (WIM) and the cold neutral medium (CNM) correlate with the star formation rate as $\sigma _\mathrm{z} \propto \Sigma _\mathrm{SFR}^a$, with a ~ 0.20. In the absence of stellar feedback, we find no correlation. The velocity dispersion of the WIM is a factor ~2.2 higher than that of the CNM, in agreement with local observations. For $\Sigma _\mathrm{SFR} \gtrsim 1.5 \times 10^{-2}\, \mathrm{M}_\odot \, \mathrm{yr}^{-1}\, \mathrm{kpc}^{-2}$ the WIM motions become supersonic.

More than 50 per cent of solar-mass stars form in multiple systems. It is therefore crucial to investigate how multiplicity affects the star and planet formation processes at the protostellar stage. We report continuum and C¹⁸O (2-1) observations of the VLA 1623-2417 protostellar system at 50 au angular resolution as part of the ALMA (Atacama Large Millimeter/submillimeter Array) Large Program FAUST. The 1.3 mm continuum probes the discs of VLA 1623A, B, and W, and the circumbinary disc of the A1 + A2 binary. The C¹⁸O emission reveals, for the first time, the gas in the disc envelope of VLA 1623W. We estimate the dynamical mass of VLA 1623W, M_dyn = 0.45 ± 0.08 M_⊙, and the mass of its disc, M_disc ~ 6 × 10^-3 M_⊙. C¹⁸O also reveals streamers that extend up to 1000 au, spatially and kinematically connecting the envelope and outflow cavities of the A1 + A2 + B system with the disc of VLA 1623W. The presence of the streamers, as well as the spatial (~1300 au) and velocity (~2.2 km s^-1) offsets of VLA 1623W, suggests that either sources W and A + B formed in different cores, interacting between them, or source W has been ejected from the VLA 1623 multiple system during its formation. In the latter case, the streamers may funnel material from the envelope and cavities of VLA 1623AB on to VLA 1623W, thus concurring to set its final mass and chemical content.

The first part of this work presents the first measurement of the three-baryon femtoscopic correlations to access the final state interactions. The cumulant method was used to estimate genuine three-body effects. A negative cumulant was observed for the p-p-p system, while the p-p-Λ cumulant was compatible with zero. The second part of this work studies the secondary cosmic ray antideuteron and antihelium-3 fluxes and the transparency of the Galaxy to the propagation of such antinuclei.

The full optimization of the design and operation of instruments whose functioning relies on the interaction of radiation with matter is a super-human task, due to the large dimensionality of the space of possible choices for geometry, detection technology, materials, data-acquisition, and information-extraction techniques, and the interdependence of the related parameters. On the other hand, massive potential gains in performance over standard, "experience-driven" layouts are in principle within our reach if an objective function fully aligned with the final goals of the instrument is maximized through a systematic search of the configuration space. The stochastic nature of the involved quantum processes make the modeling of these systems an intractable problem from a classical statistics point of view, yet the construction of a fully differentiable pipeline and the use of deep learning techniques may allow the simultaneous optimization of all design parameters.

In this white paper, we lay down our plans for the design of a modular and versatile modeling tool for the end-to-end optimization of complex instruments for particle physics experiments as well as industrial and medical applications that share the detection of radiation as their basic ingredient. We consider a selected set of use cases to highlight the specific needs of different applications.

We consider a dense neutrino gas in the "fast-flavor limit" (vanishing neutrino masses). For the first time, we identify exact solutions of the nonlinear wave equation in the form of solitons. They can propagate with both subluminal or superluminal speed, the latter not violating causality. The soliton with infinite speed is a homogeneous solution and coincides with the usual fast-flavor pendulum except that it swings only once instead of being periodic. The subluminal soliton in the static limit corresponds to a one-swing "spatial pendulum." A necessary condition for such solutions to exist is a "crossed" neutrino angle distribution. Based on the Nyquist criterion, we derive a new sufficient condition without solving the dispersion relation. The solitons are very fragile; they are as unstable as the homogeneous neutrino gas alone. Moreover, in the presence of matter, only the solution survives that is homogeneous in a frame comoving with the matter current. Generally, the matter effect cannot be eliminated by transformations in flavor space, but has real physical impact.

Conformal symmetry underlies many massless quantum field theories, but little is known about the consequences of this powerful symmetry for on-shell scattering amplitudes. Working in a dimensionally-regularised ϕ³ model at the conformal fixed point, we show that the on-shell renormalised amplitudes satisfy anomalous conformal Ward identities. Each external on-shell state contributes two terms to the anomaly. The first term is proportional to the elementary field anomalous dimension, and thus involves only lower-loop information. We show that the second term can be given as the convolution of a universal collinear function and lower-order amplitudes. The computation of the conformal anomaly is therefore simpler than that of the amplitude at the same perturbative order, which gives our anomalous conformal Ward identities a strong predictive power in perturbation theory. Finally, we show that our result is also of practical importance for dimensionally-regularised amplitudes away from the conformal fixed point.

Decays into three particles are often described in terms of two-body resonances and a non-interacting spectator particle. To go beyond this simplest isobar model, crossed-channel rescattering effects need to be accounted for. We quantify the importance of these rescattering effects in three-pion systems for different decay masses and angular-momentum quantum numbers. We provide amplitude decompositions for four decay processes with total J^PC=0^-- , 1^--, 1^-+, and 2⁺⁺, all of which decay predominantly as ρ π states. Two-pion rescattering is described in terms of an Omnès function, which incorporates the ρ resonance. Inclusion of crossed-channel effects is achieved by solving the Khuri-Treiman integral equations. The unbinned log-likelihood estimator is used to determine the significance of the rescattering effects beyond two-body resonances; we compute the minimum number of events necessary to unambiguously find these in future Dalitz-plot analyses. Kinematic effects that enhance or dilute the rescattering are identified for the selected set of quantum numbers and various masses.

The HistFactory p.d.f. template is per-se independent of its implementation in ROOT and it is useful to be able to run statistical analysis outside of the ROOT, RooFit, RooStats framework. pyhf is a pure-Python implementation of that statistical model for multi-bin histogram-based analysis and its interval estimation is based on the asymptotic formulas of "Asymptotic formulae for likelihood-based tests of new physics". pyhf supports modern computational graph libraries such as TensorFlow, PyTorch, and JAX in order to make use of features such as auto-differentiation and GPU acceleration. In addition, pyhf's JSON serialization specification for HistFactory models has been used to publish 23 full probability models from published ATLAS collaboration analyses to HEPData.

We investigate the mass-metallicity relationship of star-forming galaxies by analyzing the absorption line spectra of ~200,000 galaxies in the Sloan Digital Sky Survey. The galaxy spectra are stacked in bins of stellar mass, and a population synthesis technique is applied yielding the metallicities, ages, and star formation history of the young and old stellar population together with interstellar reddening and extinction. We adopt different lengths of the initial starbursts and different initial mass functions for the calculation of model spectra of the single stellar populations contributing to the total integrated spectrum. We also allow for deviations of the ratio of extinction to reddening R _V from 3.1 and determine the value from the spectral fit. We find that burst length and R _V have a significant influence on the determination of metallicities, whereas the effect of the initial mass function is small. The R _V values are larger than 3.1. The metallicities of the young stellar population agree with extragalactic spectroscopic studies of individual massive supergiant stars and are significantly higher than those of the older stellar population. This confirms galaxy evolution models where metallicity depends on the ratio of gas to stellar mass and where this ratio decreases with time. Star formation history is found to depend on galaxy stellar mass. Massive galaxies are dominated by stars formed at early times.