MOdified Newtonian Dynamics (MOND) is an alternative to the standard Cold Dark Matter (CDM) paradigm which proposes an alteration of Newton's laws of motion at low accelerations, characterized by a universal acceleration scale a_0. It attempts to explain observations of galactic rotation curves and predicts a specific scaling relation of the baryonic and total acceleration in galaxies, referred to as the Rotational Acceleration Relation (RAR), which can be equivalently formulated as a Mass Discrepancy Acceleration Relation (MDAR). The appearance of these relations in observational data such as SPARC has lead to investigations into the existence of similar relations in cosmological simulations using the standard ΛCDM model. Here, we report the existence of an RAR and MDAR similar to that predicted by MOND in ΛCDM using a large sample of galaxies extracted from a cosmological, hydrodynamical simulation (Magneticum). Furthermore, by using galaxies in Magneticum at different redshifts, a prediction for the evolution of the inferred acceleration parameter a_0 with cosmic time is derived by fitting a MOND force law to these galaxies. In Magneticum, the best fit for a_0 is found to increase by a factor of approximately 3 from redshift z = 0 to z = 2. This offers a powerful test from cosmological simulations to distinguish between MOND and ΛCDM observationally.

The evolution of the Kelvin-Helmholtz Instability (KHI) is widely used to assess the performance of numerical methods. We employ this instability to test both the smoothed particle hydrodynamics (SPH) and the meshless finite mass (MFM) implementation in OpenGadget3. We quantify the accuracy of SPH and MFM in reproducing the linear growth of the KHI with different numerical and physical set-ups. Among them, we consider: $i)$ numerical induced viscosity, and $ii)$ physically motivated, Braginskii viscosity, and compare their effect on the growth of the KHI. We find that the changes of the inferred numerical viscosity when varying nuisance parameters such as the set-up or the number of neighbours in our SPH code are comparable to the differences obtained when using different hydrodynamical solvers, i.e. MFM. SPH reproduces the expected reduction of the growth rate in the presence of physical viscosity and recovers well the threshold level of physical viscosity needed to fully suppress the instability. In the case of galaxy clusters with a virial temperature of $3\times10^7$ K, this level corresponds to a suppression factor of $\approx10^{-3}$ of the classical Braginskii value. The intrinsic, numerical viscosity of our SPH implementation in such an environment is inferred to be at least an order of magnitude smaller (i.e. $\approx10^ {-4}$), re-ensuring that modern SPH methods are suitable to study the effect of physical viscosity in galaxy clusters.

The scale-dependent bias effect on the galaxy power spectrum is a very promising probe of the local primordial non-Gaussianity (PNG) parameter $f_{\rm NL}$, but the amplitude of the effect is proportional to $f_{\rm NL}b_{\phi}$, where $b_{\phi}$ is the linear PNG galaxy bias parameter. Our knowledge of $b_{\phi}$ is currently very limited, yet nearly all existing $f_{\rm NL}$ constraints and forecasts assume precise knowledge for it. Here, we use the BOSS DR12 galaxy power spectrum to illustrate how our uncertain knowledge of $b_{\phi}$ currently prevents us from constraining $f_{\rm NL}$ with a given statistical precision $\sigma_{f_{\rm NL}}$. Assuming different fixed choices for the relation between $b_{\phi}$ and the linear density bias $b_1$, we find that $\sigma_{f_{\rm NL}}$ can vary by as much as an order of magnitude. Our strongest bound is $f_{\rm NL} = 16 \pm 16\ (1\sigma)$, while the loosest is $f_{\rm NL} = 230 \pm 226\ (1\sigma)$ for the same BOSS data. The impact of $b_{\phi}$ can be especially pronounced because it can be close to zero. We also show how marginalizing over $b_{\phi}$ with wide priors is not conservative, and leads in fact to biased constraints through parameter space projection effects. Independently of galaxy bias assumptions, the scale-dependent bias effect can only be used to detect $f_{\rm NL} \neq 0$ by constraining the product $f_{\rm NL}b_{\phi}$, but the error bar $\sigma_{f_{\rm NL}}$ remains undetermined and the results cannot be compared with the CMB; we find $f_{\rm NL}b_{\phi} \neq 0$ with $1.6\sigma$ significance. We also comment on why these issues are important for analyses with the galaxy bispectrum. Our results strongly motivate simulation-based research programs aimed at robust theoretical priors for the $b_{\phi}$ parameter, without which we may never be able to competitively constrain $f_{\rm NL}$ using galaxy data.

Polycyclic aromatic hydrocarbons (PAHs) play a key role in the chemical and hydrodynamical evolution of the atmospheres of exoplanets and planet-forming discs. If they can survive the planet formation process, PAHs are likely to be involved in pre-biotic chemical reactions eventually leading to more complex molecules such as amino acids and nucleotides, which form the basis for life as we know it. However, the abundance and specific role of PAHs in these environments is largely unknown due to limitations in sensitivity and range of wavelength of current and previous space-borne facilities. Upcoming infrared space spectroscopy missions, such as Twinkle and Ariel, present a unique opportunity to detect PAHs in the atmospheres of exoplanets and planet-forming discs. In this work, we present synthetic observations based on conservative numerical modelling of typical planet-forming discs and a transiting hot Saturnian planet around solar-type star. Our models show that Twinkle and Ariel might both be able to detect the 3.3 $\mu$m PAH feature within reasonable observing time in discs and transiting planets, assuming that PAHs are present with an abundance of at least one-tenth of the interstellar medium value.

We present direct N-body simulations, carried out with NBODY6+ + GPU, of young and compact low-metallicity (Z = 0.0002) star clusters with 1.1 × 10⁵ stars, a velocity dispersion of ~15 $\mathrm{km\, s^{-1}}$, a half-mass radius R_h = 0.6 pc, and a binary fraction of $10{{\ \rm per\,cent}}$ including updated evolution models for stellar winds and (pulsation) pair-instability supernovae (PSNe). Within the first tens of megayears, each cluster hosts several black hole (BH) merger events which nearly cover the complete mass range of primary and secondary BH masses for current LIGO-Virgo-KAGRA gravitational wave detections. The importance of gravitational recoil is estimated statistically during post-processing analysis. We present possible formation paths of massive BHs above the assumed lower PSN mass-gap limit ($45\, {\rm M}_\odot$) into the intermediate-mass black hole (IMBH) regime ($\gt 100\, {\rm M}_\odot$) which include collisions of stars, BHs, and the direct collapse of stellar merger remnants with low core masses. The stellar evolution updates result in the early formation of heavier stellar BHs compared to the previous model. The resulting higher collision rates with massive stars support the rapid formation of massive BHs. For models assuming a high accretion efficiency for star-BH mergers, we present a first-generation formation scenario for GW190521-like events: a merger of two BHs which reached the PSN mass-gap merging with massive stars. This event is independent of gravitational recoil and therefore conceivable in dense stellar systems with low escape velocities. One simulated cluster even forms an IMBH binary (153, 173 M_⊙) which is expected to merge within a Hubble time.

We use high-precision combined strong/weak lensing and kinematics measurements of the total mass profiles of the observed galaxy clusters MACS J1206.2-0847 and Abell S1063, to constrain the relativistic sector of the general DHOST dark energy theories, which exhibit a partial breaking of the so called Vainsthein screening mechanism, on the linear level of scalar fluctuations around a cosmological background. In particular, by using the MG-MAMMPOSST framework developed in Pizzuti et al., for the kinematics analysis of member galaxies in clusters, along with lensing mass profile reconstructions, we provide new constraints on the coupling Y₂ that governs the theory's relativistic contribution to the lensing potential. The new bound from the combination of kinematics and lensing measurements of MACS 1206, $Y_2=-0.12^{+0.66}_{-0.67}$ at 2σ, provides about a two-fold improvement on previous constraints. In the case of Abell S1063, a >2σ tension with the GR expectation arises. We discuss this in some detail, and we investigate the possible sources of systematics that can explain the tension. We further discuss why the combination of kinematics of member galaxies with lensing is capable of providing much tighter bounds compared to kinematics or lensing alone, and we explain how the number density profile of tracers, as well as the choice of the velocity anisotropy profile, affects the final results.

We investigate the final collapse of rotating and non-rotating pulsational pair-instability supernova progenitors with zero-age-main-sequence masses of 60, 80, and 115 M_⊙ and iron cores between 2.37 and 2.72 M_⊙ by 2D hydrodynamics simulations. Using the general relativistic NADA-FLD code with energy-dependent three-flavour neutrino transport by flux-limited diffusion allows us to follow the evolution beyond the moment when the transiently forming neutron star (NS) collapses to a black hole (BH), which happens within 350-580 ms after bounce in all cases. Because of high neutrino luminosities and mean energies, neutrino heating leads to shock revival within ≲ 250 ms post bounce in all cases except the rapidly rotating 60 M_⊙ model. In the latter case, centrifugal effects support a 10 per cent higher NS mass but reduce the radiated neutrino luminosities and mean energies by ~20 per cent and ~10 per cent, respectively, and the neutrino-heating rate by roughly a factor of two compared to the non-rotating counterpart. After BH formation, the neutrino luminosities drop steeply but continue on a 1-2 orders of magnitude lower level for several 100 ms because of aspherical accretion of neutrino and shock-heated matter, before the ultimately spherical collapse of the outer progenitor shells suppresses the neutrino emission to negligible values. In all shock-reviving models BH accretion swallows the entire neutrino-heated matter and the explosion energies decrease from maxima around 1.5 × 10⁵¹ erg to zero within a few seconds latest. Nevertheless, the shock or a sonic pulse moves outward and may trigger mass-loss, which we estimate by long-time simulations with the PROMETHEUS code. We also provide gravitational-wave signals.

We explicitly carry out the symplectic quantization of a family of multifield generalized Proca (GP) electrodynamics theories. In the process, we provide an independent derivation of the so-called secondary constraint enforcing relations—consistency conditions that significantly restrict the allowed interactions in multifield settings already at the classical level. Additionally, we unveil the existence of quantum consistency conditions, which apply in both single- and multifield GP scenarios. Our newly found conditions imply that not all classically well-defined (multi-)GP theories are amenable to quantization. The extension of our results to the most general multi-GP class is conceptually straightforward, albeit algebraically cumbersome.

We compute the three-loop helicity amplitudes for the scattering of four gluons in QCD. We employ projectors in the 't Hooft-Veltman scheme and construct the amplitudes from a minimal set of physical building blocks, which allows us to keep the computational complexity under control. We obtain relatively compact results that can be expressed in terms of harmonic polylogarithms. In addition, we consider the Regge limit of our amplitude and extract the gluon Regge trajectory in full three-loop QCD. This is the last missing ingredient required for studying single-Reggeon exchanges at next-to-next-to-leading logarithmic accuracy.

We evaluate the leading-order hadronic vacuum polarization contribution to the anomalous magnetic moment of the muon with two light flavors in minimal hard-wall and soft-wall holographic QCD models, as well as in simple generalizations thereof, and compare it to the rather precise results available from dispersive and lattice approaches. While holographic QCD cannot be expected to shed light on the existing small discrepancies between the latter, this comparison in turn provides useful information on the holographic models, which have been used to evaluate hadronic light-by-light contributions where errors in data-driven and lattice approaches are more sizable. In particular, in the hard-wall model that has recently been used to implement the Melnikov-Vainshtein short-distance constraint on hadronic light-by-light contributions, a matching of the hadronic vacuum polarization to the data-driven approach points to the same correction of parameters that has been proposed recently in order to account for next-to-leading-order effects.

Red supergiant (RSGs) are cool massive stars in a late phase of their evolution when the stellar envelope becomes fully convective. They are the brightest stars in the universe at infrared light and can be detected in galaxies far beyond the Local Group, allowing for accurate determination of chemical composition of galaxies. The study of their physical properties is extremely important for various phenomena including the final fate of massive stars as type II supernovae and gravitational wave progenitors. We explore the well-studied nearby young stellar cluster chi Per. Using Gaia EDR3 data, we find the distance of the cluster (d = 2.260+-0.020 kpc). We then investigate the variability of the convection-related surface structure as a source for parallax measurement uncertainty. We use state-of-the-art 3D radiative hydrodynamics simulations with CO5BOLD and the post-processing radiative transfer code OPTIM3D to compute intensity maps in the Gaia G photometric system. We calculate the variabiltiy, as a function of time, of the intensity-weighted mean from the synthetic maps. We then select the RSG stars in the cluster and compare their uncertainty on parallaxes to the predictions of photocentre displacements. The synthetic maps of RSG show extremely irregular and temporal variable surfaces due to convection-related dynamics. Consequentially, the position of the photo-center varies during Gaia measurements between 0.033 and 0.130 AU (up to 5% of the corresponding simulation stellar radius). We argue that the variability of the convection-related surface structures accounts for a substantial part of the Gaia EDR3 parallax error of the RSG sample. We suggest that the variation of the uncertainty on Gaia parallax could be exploited quantitatively using appropriate 3D simulations to extract, in a unique way, important information about the stellar dynamics and parameters of RSG stars.

A sub-fraction of dark matter or new particles trapped inside celestial objects can significantly alter their macroscopic properties. We investigate the new physics imprint on celestial objects by using a generic framework to solve the Tolman-Oppenheimer-Volkoff (TOV) equations for up to two fluids. We test the impact of populations of new particles on celestial objects, including the sensitivity to self-interaction sizes, new particle mass, and net population mass. Applying our setup to neutron stars and boson stars, we find rich phenomenology for a range of these parameters, including the creation of extended atmospheres. These atmospheres are detectable by their impact on the tidal love number, which can be measured at upcoming gravitational wave experiments such as Advanced LIGO, the Einstein Telescope, and LISA. We release our calculation framework as a publicly available code, allowing the TOV equations to be generically solved for arbitrary new physics models in novel and admixed celestial objects.

The scale-dependent bias effect on the galaxy power spectrum is a very promising probe of the local primordial non-Gaussianity (PNG) parameter $f_{\rm NL}$, but the amplitude of the effect is proportional to $f_{\rm NL}b_{\phi}$, where $b_{\phi}$ is the linear PNG galaxy bias parameter. Our knowledge of $b_{\phi}$ is currently very limited, yet nearly all existing $f_{\rm NL}$ constraints and forecasts assume precise knowledge for it. Here, we use the BOSS DR12 galaxy power spectrum to illustrate how our uncertain knowledge of $b_{\phi}$ currently prevents us from constraining $f_{\rm NL}$ with a given statistical precision $\sigma_{f_{\rm NL}}$. Assuming different fixed choices for the relation between $b_{\phi}$ and the linear density bias $b_1$, we find that $\sigma_{f_{\rm NL}}$ can vary by as much as an order of magnitude. Our strongest bound is $f_{\rm NL} = 16 \pm 16\ (1\sigma)$, while the loosest is $f_{\rm NL} = 230 \pm 226\ (1\sigma)$ for the same BOSS data. The impact of $b_{\phi}$ can be especially pronounced because it can be close to zero. We also show how marginalizing over $b_{\phi}$ with wide priors is not conservative, and leads in fact to biased constraints through parameter space projection effects. Independently of galaxy bias assumptions, the scale-dependent bias effect can only be used to detect $f_{\rm NL} \neq 0$ by constraining the product $f_{\rm NL}b_{\phi}$, but the error bar $\sigma_{f_{\rm NL}}$ remains undetermined and the results cannot be compared with the CMB; we find $f_{\rm NL}b_{\phi} \neq 0$ with $1.6\sigma$ significance. We also comment on why these issues are important for analyses with the galaxy bispectrum. Our results strongly motivate simulation-based research programs aimed at robust theoretical priors for the $b_{\phi}$ parameter, without which we may never be able to competitively constrain $f_{\rm NL}$ using galaxy data.

We generalise existing constraints on primordial black holes to dark objects with extended sizes using the aLIGO design sensitivity. We show that LIGO is sensitive to dark objects with radius $O(10-10^3~{\rm km})$ if they make up more than $\sim O(10^{-2}-10^{-3})$ of dark matter.

One of the most energetic events in the Universe are core-collapse Supernovae (SNe), where almost all the star's binding energy is released as neutrinos. These particles are direct probes of the processes occurring in the stellar core and provide unique insights into the gravitational collapse. RES-NOVA will revolutionize how we detect neutrinos from astrophysical sources, by deploying the first ton-scale array of cryogenic detectors made from archaeological lead. Pb offers the highest neutrino interaction cross-section via coherent elastic neutrino-nucleus scattering (CE$\nu$NS). Such process will enable RES-NOVA to be equally sensitive to all neutrino flavors. For the first time, we propose to use archaeological Pb as sensitive target material in order to achieve an ultra-low background level in the region of interest (\textit{O}(1keV)). All these features make possible the deployment of the first cm-scale neutrino telescope for the investigation of astrophysical sources. In this contribution, we will characterize the radiopurity level and the performance of a small-scale proof-of-principle detector of RES-NOVA, consisting in a PbWO$_4$ crystal made from archaeological-Pb operated as cryogenic detector.

High-precision measurements require optimal setups and analysis tools to achieve continuous improvements. Systematic corrections need to be modeled with high accuracy and known uncertainty to reconstruct underlying physical phenomena. To this end, we present Gaussian processes for modeling experiments and usage with Bayesian optimization, on the example of an electron energy detector, achieving optimal performance. We demonstrate the method's strengths and outline stochastic variational Gaussian processes for physics applications with large data sets, enabling new solutions for current problems.

We derive a new upper bound on the tensor-to-scalar ratio parameter $r$ using the frequentist profile likelihood method. We vary all the relevant cosmological parameters of the $\Lambda$CDM model, as well as the nuisance parameters. Unlike the Bayesian analysis using Markov Chain Monte Carlo (MCMC), our analysis is independent of the choice of priors. Using $Planck$ Public Release 4, BICEP/Keck Array 2018, $Planck$ CMB lensing, and BAO data, we find an upper limit of $r<0.037$ at 95% C.L., similar to the Bayesian MCMC result of $r<0.038$ for a flat prior on $r$ and a conditioned $Planck$ lowlEB covariance matrix.

Supernovae (SNe) are among the most energetic events in the universe still far from being fully understood. An early and prompt detection of neutrinos is a one-time opportunity for the realization of the first multi-messenger observation of these events. In this work, we present the prospects of detecting neutrinos produced before (pre-SN) and during a SN while running an advanced cryogenic detector. The recent advancements of the cryogenic detector technique and the discovery of coherent elastic neutrino-nucleus scattering offer a wealth of opportunities in neutrino detection. The combination of the excellent energy resolution of this experimental technique, with the high cross section of this detection channel and its equal sensitivity to all neutrino flavors enables the realization of highly sensitive cm-scale neutrino telescopes, as the newly proposed RES-NOVA experiment. We present a detailed study on the detection promptness of pre-SN and SN neutrino signals, with direct comparisons among different classes of test statistics. While the well-established Poisson test offers in general best performance under optimal conditions, the non-parametric Recursive Product of Spacing statistical test (RPS) is more robust and ideal for triggering astrophysical neutrino signals with no specific prior knowledge. Based on our statistical tests the RES-NOVA experiment is able to identify SN neutrino signals at a 15 kpc distance with 95% of success rate, and pre-SN signal as far as 480 pc with a pre-warn time of the order of 10 s. These results demonstrate the potential of RPS for the identification of neutrino signals and the physics reach of the RES-NOVA experiment.

The current cosmological model requires new physics beyond the standard model of elementary particles and fields, such as dark matter and dark energy. Their nature is unknown and so is that of the initial fluctuations in the early Universe that led to the creation of the cosmic structure we see today. Polarized light of the cosmic microwave background (CMB) may hold the answer to these fundamental questions. Here, I discuss two phenomena that could be uncovered in CMB observations. First, if the physics behind dark matter and dark energy violates parity symmetry, their coupling to photons should have rotated the plane of linear polarization as the CMB photons have been travelling for more than 13 billion years. This effect is known as `cosmic birefringence'. A tantalizing hint of such a signal has been found with a statistical significance of 3σ. Second, the period of accelerated expansion in the very early Universe, called `cosmic inflation', might have produced a stochastic background of primordial gravitational waves (as yet unobserved). These might have been generated by vacuum fluctuations in spacetime or by matter fields and could be measurable in the CMB polarization. The goal of observing these two phenomena will influence how data from future CMB experiments are collected, calibrated and analysed.

This summary reviews contributions to the CKM 2021 workshop in Working Group 4. In particular, theoretical and experimental progress in determining $B$ meson mixing properties are discussed.

First information on the timelike electromagnetic structure of baryons in the second resonance region has been obtained from measurements of invariant mass and angular distributions in the quasi-free reaction $\pi^- p \to nee$ at $\sqrt{s_{\pi^- p}}$ = 1.49 GeV with the High Acceptance Di-Electron Spectrometer (HADES) detector at GSI using the pion beam impinging on a CH$_2$ target. We find a total cross section $\sigma (\pi^- p \to nee) = 2.97 \pm 0.07^{data} \pm 0.21^{acc} \pm 0.31^{\rm{Z}_{\rm{eff}}} \mu$b. Combined with the Partial Wave Analysis of the concurrently measured two-pion channel, these data sets provide a crucial test of Vector Meson Dominance (VMD) inspired models. The commonly used "strict VMD" approach strongly overestimates the $e^+e^-$ yield. Instead, approaches based on a VMD amplitude vanishing at small $e^+e^-$ invariant masses supplemented coherently by a direct photon amplitude provide a better agreement. A good description of the data is also obtained using a calculation of electromagnetic timelike baryon transition form factors in a covariant spectator-quark model, demonstrating the dominance of meson cloud effects. The angular distributions of $e^+e^-$ pairs demonstrate the contributions of virtual photons with longitudinal polarization, in contrast to real photons. The virtual photon angular dependence supports the dominance of J=3/2, I=1/2 contributions observed in both the $\gamma^{\star} n$ and the $\pi \pi n$ channels.

We study the effects of a fixed de Sitter geometry background in scenarios of false vacuum decay. It is currently understood that bubble nucleation processes associated with first order phase transitions are particularly important in cosmology. The geometry of spacetime complicates the interpretation of the decay rate of a metastable vacuum. However, the effects of curvature can still be studied in the particular case where backreaction is neglected. We compute the imaginary part of the action in de Sitter space, including the one-loop and the gradient corrections. We use two independent methodologies and quantify the size of the corrections without any assumptions on the thickness of the wall of the scalar background configuration.

While $CP$ violation has never been observed in the strong interactions, the QCD Lagrangian admits a $CP$-odd topological interaction proportional to the so called $\theta$ angle, which weighs the contributions to the partition function from different topological sectors. The observational bounds are usually interpreted as demanding a severe tuning of $\theta$ against the phases of the quark masses, which constitutes the strong $CP$ problem. Here we report on recent challenges to this view based on a careful treatment of boundary conditions in the path integral and of the limit of infinite spacetime volume, which leads to $\theta$ dropping out of fermion correlation functions and becoming unobservable, implying that $CP$ is preserved in QCD.

We revisit the joint constraints in the mixed hot dark matter scenario in which both thermally produced QCD axions and relic neutrinos are present. Upon recomputing the cosmological axion abundance via recent advances in the literature, we improve the state-of-the-art analyses and provide updated bounds on axion and neutrino masses. By avoiding approximate methods, such as the instantaneous decoupling approximation, and limitations due to the limited validity of the perturbative approach in QCD that forced to artificially divide the constraints from the axion-pion and the axion-gluon production channels, we find robust and self-consistent limits. We investigate the two most popular axion frameworks: KSVZ and DFSZ. From Big Bang Nucleosynthesis (BBN) light element abundances data we find for the KSVZ axion $\Delta N_{\rm eff}<0.31$ and an axion mass bound $m_a < 0.53 $ eV (i.e., a bound on the axion decay constant $f_a > 1.07 \times 10^7$ GeV) both at $95\%$ CL. These BBN bounds are improved to $\Delta N_{\rm eff}<0.14$ and $m_a< 0.16$ eV ($f_a > 3.56 \times 10^7$ GeV) if a prior on the baryon energy density from Cosmic Microwave Background (CMB) data is assumed. When instead considering cosmological observations from the CMB temperature, polarization and lensing from the Planck satellite combined with large scale structure data we find $\Delta N_{\rm eff}<0.23$, $m_a< 0.28$ eV ($f_a > 2.02 \times 10^7$ GeV) and $\sum m_\nu < 0.16$ eV at $95\%$ CL. This corresponds approximately to a factor of $5$ improvement in the axion mass bound with respect to the existing limits. Very similar results are obtained for the DFSZ axion. We also forecast upcoming observations from future CMB and galaxy surveys, showing that they could reach percent level errors for $m_a\sim 1$ eV.

We present [CII] synthetic observations of smoothed particle hydrodynamics (SPH) simulations of a dwarf galaxy merger. The merging process varies the star-formation rate by more than three orders of magnitude. Several star clusters are formed, the feedback of which disperses and unbinds the dense gas through expanding HII regions and supernova (SN) explosions. For galaxies with properties similar to the modelled ones, we find that the [CII] emission remains optically thin throughout the merging process. We identify the Warm Neutral Medium ($3<\log T_{\rm gas}4$ with $\chi_{\rm HI}>2\chi_{\rm H2}$) to be the primary source of [CII] emission ($\sim58\%$ contribution), although at stages when the HII regions are young and dense (during star cluster formation or SNe in the form of ionized bubbles) they can contribute $\gtrsim50\%$ to the total [CII] emission. We find that the [CII]/FIR ratio decreases due to thermal saturation of the [CII] emission caused by strong FUV radiation fields emitted by the massive star clusters, leading to a [CII]-deficit medium. We investigate the [CII]-SFR relation and find an approximately linear correlation which agrees well with observations, particularly those from the Dwarf Galaxy Survey. Our simulation reproduces the observed trends of [CII]/FIR versus $\Sigma_{\rm SFR}$ and $\Sigma_{\rm FIR}$, and it agrees well with the Kennicutt relation of SFR-FIR luminosity. We propose that local peaks of [CII] in resolved observations may provide evidence for ongoing massive cluster formation.

Intracellular protein patterns regulate a variety of vital cellular processes such as cell division and motility, which often involve dynamic changes of cell shape. 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 resulting rich 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 that do not occur in systems with a fixed membrane shape. Our work 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.

Dark matter (DM) with self-interactions is a promising solution for the small-scale problems of the standard cosmological model. Here we perform the first cosmological simulation of frequent DM self-interactions, corresponding to small-angle DM scatterings. The focus of our analysis lies in finding and understanding differences to the traditionally assumed rare DM (large-angle) self scatterings. For this purpose, we compute the distribution of DM densities, the matter power spectrum, the two-point correlation function and the halo and subhalo mass functions. Furthermore, we investigate the density profiles of the DM haloes and their shapes. We find that overall large-angle and small-angle scatterings behave fairly similarly with a few exceptions. In particular, the number of satellites is considerably suppressed for frequent compared to rare self-interactions with the same cross-section. Overall we observe that while differences between the two cases may be difficult to establish using a single measure, the degeneracy may be broken through a combination of multiple ones. For instance, the combination of satellite counts with halo density or shape profiles could allow discriminating between rare and frequent self-interactions. As a by-product of our analysis, we provide - for the first time - upper limits on the cross-section for frequent self-interactions.

Three-dimensional correlations of the Lyman-$\alpha$ (Ly$\alpha$) forest and cross correlations between the Ly$\alpha$ forest and quasars have been measured on large scales, allowing a precise measurement of the baryon acoustic oscillation (BAO) feature at redshifts $z>2$. These 3D correlations are often modelled using linear perturbation theory, but full-shape analyses to extract cosmological information beyond BAO will require more realistic models capable of describing non-linearities present at smaller scales. We present a measurement of the Ly$\alpha$ forest flux power spectrum from large hydrodynamic simulations -- the Sherwood simulations -- and compare it to different models describing the small-scale deviations from linear theory. We confirm that the model presented in Arinyo-i-Prats et al. (2015) fits the measured 3D power up to $k=10\, h\rm{Mpc^{-1}}$ with an accuracy better than 5%, and show that the same model can also describe the 1D correlations with similar precision. We also present, for the first time, an equivalent study for the cross-power spectrum of halos with the Ly$\alpha$ forest, and we discuss different challenges we face when modelling the cross-power spectrum beyond linear scales. We make all our measured power spectra public in \url{https://github.com/andreufont/sherwood_p3d}. This study is a step towards joint analyses of 1D and 3D flux correlations, and towards using the quasar-Ly$\alpha$ cross-correlation beyond BAO analyses.

Based on the Simplified Differential Equations approach, we present results for the two-loop non-planar hexa-box families of master integrals. We introduce a new approach to obtain the boundary terms and establish a one-dimensional integral representation of the master integrals in terms of Generalised Polylogarithms, when the alphabet contains non-factorisable square roots. The results are relevant to the study of NNLO QCD corrections for W, Z and Higgs-boson production in association with two hadronic jets.

In this decade one expects a very significant progress in measuring the branching ratios for several rare $K$ and $B$ decays, in particular for the decays $K^+\to\pi^+\nu\bar\nu$, $K_L\to\pi^0\nu\bar\nu$, $B_s\to\mu^+\mu^+$ and $B_d\to\mu^+\mu^+$. On the theory side a very significant progress on calculating these branching ratios has been achieved in the last thirty years culminating recently in rather precise SM predictions for them. It is then unfortunate that some papers still cite the results for $K^+\to\pi^+\nu\bar\nu$ and $K_L\to\pi^0\nu\bar\nu$ presented by us in 2015. They are clearly out of date. Similar comments apply to predictions for $B_{s,d}\to\mu^+\mu^-$. In this note I want to stress again that, in view of the tensions between various determinations of $V_{cb}$ in tree-level decays, presently, the only trustable SM predictions for the branching ratios in question can be obtained by eliminating their dependence on the CKM parameters with the help of $|\varepsilon_K|$, $\Delta M_s$, $\Delta M_d$ and $S_{\psi K_S}$, evaluated in the SM. In this context I am astonished by statements made by some computer code practitioners that setting in this strategy these four $\Delta F=2$ observables to their experimental values is an assumption. The goal of this strategy is not to make an overall SM fit but to predict the SM branching ratios. In the SM there are no new physics (NP) contributions to $\Delta F=2$ transitions and no assumption on the absence of NP is needed. Moreover, presently NP is not required to describe simultaneously the very precise data on $|\varepsilon_K|$, $\Delta M_s$, $\Delta M_d$ and $S_{\psi K_S}$. This strategy for obtaining true SM predictions for rare decay branching ratios is moreover not polluted by hadronic uncertainies and observed anomalies in semi-leptonic decays used often in global analyses.

Using the potential non-relativistic quantum chromodynamics (pNRQCD) effective field theory, we derive a Lindblad equation for the evolution of the heavy-quarkonium reduced density matrix that is accurate to next-to-leading order (NLO) in the ratio of the binding energy of the state to the temperature of the medium. The resulting NLO Lindblad equation can be used to more reliably describe heavy-quarkonium evolution in the quark-gluon plasma at low temperatures compared to the leading-order truncation. For phenomenological application, we numerically solve the resulting NLO Lindblad equation using the quantum trajectories algorithm. To achieve this, we map the solution of the three-dimensional Lindblad equation to the solution of an ensemble of one-dimensional Schrödinger evolutions with Monte-Carlo sampled quantum jumps. Averaging over the Monte-Carlo sampled quantum jumps, we obtain the solution to the NLO Lindblad equation without truncation in the angular momentum quantum number of the states considered. We also consider the evolution of the system using only the complex effective Hamiltonian without stochastic jumps and find that this provides a reliable approximation for the ground state survival probability at LO and NLO. Finally, we make comparisons with our prior leading-order pNRQCD results and experimental data available from the ATLAS, ALICE, and CMS collaborations.

We study gravothermal evolution of dark matter halos in the presence of differential self-scattering that has strong velocity and angular dependencies. We design controlled N-body simulations to model Rutherford and Moller scatterings in the halo, and follow its evolution in both core-expansion and -collapse phases. The simulations show the commonly-used transfer cross section underestimates the effects of dark matter self-interactions, but the viscosity cross section provides a good approximation for modeling angular-dependent dark matter scattering. We investigate thermodynamic properties of the halo, and find that the three moments of the Boltzmann equation under the fluid approximation are satisfied. We further propose a constant effective cross section, which integrates over the halo's characteristic velocity dispersion with weighting kernels motivated by kinetic theory of heat conduction. The effective cross section provides an approximation to differential self-scattering for most of the halo evolution. However, it can significantly underestimate the growth rate of the central density at late stages of the collapse phase. This indicates that constant and velocity-dependent dark matter self-interactions are fundamentally different, as for the latter the cross section evolves with the halo dynamically, boosting the collapse. This feature may help test different self-interacting dark matter models.

The evolution of the Kelvin-Helmholtz Instability (KHI) is widely used to assess the performance of numerical methods. We employ this instability to test both the smoothed particle hydrodynamics (SPH) and the meshless finite mass (MFM) implementation in OpenGadget3. We quantify the accuracy of SPH and MFM in reproducing the linear growth of the KHI with different numerical and physical set-ups. Among them, we consider: $i)$ numerical induced viscosity, and $ii)$ physically motivated, Braginskii viscosity, and compare their effect on the growth of the KHI. We find that the changes of the inferred numerical viscosity when varying nuisance parameters such as the set-up or the number of neighbours in our SPH code are comparable to the differences obtained when using different hydrodynamical solvers, i.e. MFM. SPH reproduces the expected reduction of the growth rate in the presence of physical viscosity and recovers well the threshold level of physical viscosity needed to fully suppress the instability. In the case of galaxy clusters with a virial temperature of $3\times10^7$ K, this level corresponds to a suppression factor of $\approx10^{-3}$ of the classical Braginskii value. The intrinsic, numerical viscosity of our SPH implementation in such an environment is inferred to be at least an order of magnitude smaller (i.e. $\approx10^ {-4}$), re-ensuring that modern SPH methods are suitable to study the effect of physical viscosity in galaxy clusters.

Supernovae (SNe) are among the most energetic events in the universe still far from being fully understood. An early and prompt detection of neutrinos is a one-time opportunity for the realization of the first multi-messenger observation of these events. In this work, we present the prospects of detecting neutrinos produced before (pre-SN) and during a SN while running an advanced cryogenic detector. The recent advancements of the cryogenic detector technique and the discovery of coherent elastic neutrino-nucleus scattering offer a wealth of opportunities in neutrino detection. The combination of the excellent energy resolution of this experimental technique, with the high cross section of this detection channel and its equal sensitivity to all neutrino flavors enables the realization of highly sensitive cm-scale neutrino telescopes, as the newly proposed RES-NOVA experiment. We present a detailed study on the detection promptness of pre-SN and SN neutrino signals, with direct comparisons among different classes of test statistics. While the well-established Poisson test offers in general best performance under optimal conditions, the non-parametric Recursive Product of Spacing statistical test (RPS) is more robust and ideal for triggering astrophysical neutrino signals with no specific prior knowledge. Based on our statistical tests the RES-NOVA experiment is able to identify SN neutrino signals at a 15 kpc distance with 95% of success rate, and pre-SN signal as far as 480 pc with a pre-warn time of the order of 10 s. These results demonstrate the potential of RPS for the identification of neutrino signals and the physics reach of the RES-NOVA experiment.

We perform the first calculation of form factors in the semileptonic decays B → D₁(2420)ℓν_ℓ and B → D₁^'(2430)ℓν_ℓ using QCD light-cone sum rules (LCSRs) with B-meson distribution amplitudes. In this calculation the c-quark mass is finite. Analytical expressions for two-particle contributions up to twist four are obtained. To disentangle the D₁ and D₁^' contributions in the LCSRs, we suggest a novel approach that introduces a combination of two interpolating currents for these charmed mesons. To fix all the parameters in the LCSRs, we use the two-point QCD sum rules for the decay constants of D₁ and D₁^' mesons augmented by a single experimental input, that is the B → D₁(2420)ℓν_ℓ decay width. We provide numerical results for all B → D₁ and B → D₁^' form factors. As a byproduct, we also obtain the D₁- and D₁^'-meson decay constants and predict the lepton-flavour universality ratios R(D₁) and R(D₁^').

The lack of convergence of the convolution integrals appearing in next-to-leading-power (NLP) factorization theorems prevents the applications of existing methods to resum power-suppressed large logarithmic corrections in collider physics. We consider thrust distribution in the two-jet region for the flavour-nonsinglet off-diagonal contribution, where a gluon-initiated jet recoils against a quark-antiquark pair, which is power-suppressed. With the help of operatorial endpoint factorization conditions, we obtain a factorization formula, where the individual terms are free from endpoint divergences in convolutions and can be expressed in terms of renormalized hard, soft and collinear functions in four dimensions. This allows us to perform the first resummation of the endpoint-divergent SCET$_{\rm I}$ observables at the leading logarithmic accuracy using exclusively renormalization-group methods. The presented approach relies on universal properties of the soft and collinear limits and may serve as a paradigm for the systematic NLP resummation for other $1\to 2$ and $2\to 1$ collider physics processes.

The Euclid mission $-$ with its spectroscopic galaxy survey covering a sky area over $15\,000 \ \mathrm{deg}^2$ in the redshift range $0.9<z<1.8\ -$ will provide a sample of tens of thousands of cosmic voids. This paper explores for the first time the constraining power of the void size function on the properties of dark energy (DE) from a survey mock catalogue, the official Euclid Flagship simulation. We identify voids in the Flagship light-cone, which closely matches the features of the upcoming Euclid spectroscopic data set. We model the void size function considering a state-of-the art methodology: we rely on the volume conserving (Vdn) model, a modification of the popular Sheth & van de Weygaert model for void number counts, extended by means of a linear function of the large-scale galaxy bias. We find an excellent agreement between model predictions and measured mock void number counts. We compute updated forecasts for the Euclid mission on DE from the void size function and provide reliable void number estimates to serve as a basis for further forecasts of cosmological applications using voids. We analyse two different cosmological models for DE: the first described by a constant DE equation of state parameter, $w$, and the second by a dynamic equation of state with coefficients $w_0$ and $w_a$. We forecast $1\sigma$ errors on $w$ lower than the $10\%$, and we estimate an expected figure of merit (FoM) for the dynamical DE scenario $\mathrm{FoM}_{w_0,w_a} = 17$ when considering only the neutrino mass as additional free parameter of the model. The analysis is based on conservative assumptions to ensure full robustness, and is a pathfinder for future enhancements of the technique. Our results showcase the impressive constraining power of the void size function from the Euclid spectroscopic sample, both as a stand-alone probe, and to be combined with other Euclid cosmological probes.

We derive a new upper bound on the tensor-to-scalar ratio parameter $r$ using the frequentist profile likelihood method. We vary all the relevant cosmological parameters of the $\Lambda$CDM model, as well as the nuisance parameters. Unlike the Bayesian analysis using Markov Chain Monte Carlo (MCMC), our analysis is independent of the choice of priors. Using $Planck$ Public Release 4, BICEP/Keck Array 2018, $Planck$ CMB lensing, and BAO data, we find an upper limit of $r<0.037$ at 95% C.L., similar to the Bayesian MCMC result of $r<0.038$ for a flat prior on $r$ and a conditioned $Planck$ lowlEB covariance matrix.

Recent observations have shown that the atmospheres of ultra hot Jupiters (UHJs) commonly possess temperature inversions, where the temperature increases with increasing altitude. Nonetheless, which opacity sources are responsible for the presence of these inversions remains largely observationally unconstrained. We used LBT/PEPSI to observe the atmosphere of the UHJ KELT-20 b in both transmission and emission in order to search for molecular agents which could be responsible for the temperature inversion. We validate our methodology by confirming a previous detection of Fe I in emission at $15.1\sigma$; however, we are unable to reproduce published detections of Fe II, Cr I, or Si I. We attribute the non-detection of Si I to the lack of lines in our bandpass, but the non-detections of Fe II and Cr I are puzzling due to our much higher signal-to-noise ratio than previous works. Our search for the inversion agents TiO, VO, FeH, and CaH results in non-detections. Using injection-recovery testing we set $4\sigma$ upper limits upon the volume mixing ratios for these constituents as low as $\sim1\times10^{-10}$ for TiO. For TiO, VO, and CaH, our limits are much lower than expectations from an equilibrium chemical model, while FeH is lower than the expectations only from a super-Solar metallicity model. We thus rule out TiO, VO, and CaH as the source of the temperature inversion in KELT-20 b, while FeH is disfavored only if KELT-20 b possesses a high-metallicity atmosphere.

We study gauge theories of background fields associated to BRST quantized spinning particle models and identify background-independent algebraic structures which allow to systematically reduce the spectrum of fields and subject some of them to dynamical equations of motion. More specifically, we construct a manifestly background-independent extension of the model based on N = 2 spinning particle. The resulting system describes an on-shell spin-1 field coupled to off-shell background fields including metric and dilaton. Tensoring with a given Lie algebra results in a non-abelian extension of the model.

Proteins control many vital functions in living cells, such as cell growth and cell division. Reliable coordination of these functions requires the spatial and temporal organization of proteins inside cells, which encodes information about the cell's geometry and the cell-cycle stage. The study of such protein patterns has long focused around formation in uniform environments. However, in recent years, it has become evident that spatial heterogeneities are essential for protein patterning, and various guiding cues in the cell or at the cell boundary can be exploited to reliably control protein pattern formation. We review how protein patterns are guided by cell size and shape, by other protein patterns that act as templates, and by the mechanical properties of the cell. The basic mechanisms of guided pattern formation are elucidated with reference to observations in various biological model organisms. We posit that understanding the controlled formation of protein patterns in cells will be an essential part of understanding information processing in living systems.

Context. Galaxy clusters grow through mergers and the accretion of substructures along large-scale filaments. Many of the missing baryons in the local Universe may reside in such filaments as the warm-hot intergalactic medium (WHIM).
Aims: SRG/eROSITA performance verification observations revealed that the binary cluster Abell 3391/3395 and the Northern Clump (the MCXC J0621.7-5242 galaxy cluster) are aligning along a cosmic filament in soft X-rays, similarly to what has been seen in simulations before. We aim to understand the dynamical state of the Northern Clump as it enters the atmosphere (3 × R₂₀₀) of Abell 3391.
Methods: We analyzed joint eROSITA, XMM-Newton, and Chandra observations to probe the morphological, thermal, and chemical properties of the Northern Clump from its center out to a radius of 988 kpc (R₂₀₀). We utilized the ASKAP/EMU radio data, the DECam optical image, and the Planck y-map to study the influence of the wide-angle tail (WAT) radio source on the Northern Clump's central intracluster medium. Using eROSITA data, we also analyzed the gas properties of the Northern Filament, the region between the virial radii of the Northern Clump and the A3391 cluster. From the Magneticum simulation, we identified an analog of the A3391/95 system along with an infalling group resembling the Northern Clump.
Results: The Northern Clump is a weak cool-core cluster centered on a WAT radio galaxy. The gas temperature over 0.2-0.5R₅₀₀ is k_BT₅₀₀ = 1.99 ± 0.04 keV. We employed the mass-temperature (M - T) scaling relation and obtained a mass estimate of M₅₀₀ = (7.68 ± 0.43) × 10¹³ M_⊙ and R₅₀₀ = (63 6 ± 12) kpc. Its X-ray atmosphere has a boxy shape and deviates from spherical symmetry. We identify a southern surface brightness edge, likely caused by subsonic motion relative to the filament gas in the southern direction. At ~R₅₀₀, the southern atmosphere (infalling head) appears to be 42% hotter than its northern atmosphere. We detect a downstream tail pointing toward the north with a projected length of ~318 kpc, plausibly the result of ram pressure stripping. Through a two-temperature fit, we identify a cooler component in the Northern Filament with k_BT = 0.68_{- 0.64}^{+ 0.38} keV <!--inline-formula id="FI1"><alternatives><![CDATA[{k_{B}}T = 0.68_{- 0.64}^{+ 0.38}{{keV}}]]>kBT=0.68−0.64+0.38keV<inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" id="img_eq1" mime-subtype="png" mimetype="image" xlink:href="aa41415-21-eq1.png"/></alternatives> and n_e = 1.99_-1.24^+0.88 × 10^-5cm^-3, <!--inline-formula id="FI2"><alternatives><![CDATA[{n_e}1.99_{- 1.24}^{+ 0.88} × {10^{- 5}}{{c}}{{{m}}^{- 3}}]]>ne1.99−1.24+0.88×10−5cm−3<inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" id="img_eq2" mime-subtype="png" mimetype="image" xlink:href="aa41415-21-eq2.png"/></alternatives> which are consistent within the expected ranges of WHIM properties. The analog group in the Magneticum simulation is experiencing changes in its gas properties and a shift between the position of the halo center and that of the bound gas, while approaching the main cluster pair.
Conclusions: The Northern Clump is a dynamically active system and far from being relaxed. Its atmosphere is affected by an interaction with the WAT and by gas sloshing or its infall toward Abell 3391 along the filament, consistent with the analog group-size halo in the Magneticum simulation.

The coming generation of galaxy surveys will provide measurements of galaxy clustering with unprecedented accuracy and data size, which will allow us to test cosmological models at much higher precision than achievable previously. This means that we must have more accurate theoretical predictions to compare with future observational data. As a first step towards more accurate modelling of the redshift space distortions (RSD) of small-scale galaxy clustering in modified gravity (MG) cosmologies, we investigate the validity of the so-called Skew-T (ST) probability distribution function (PDF) of halo pairwise peculiar velocities in these models. We show that, combined with the streaming model of RSD, the ST PDF substantially improves the small-scale predictions by incorporating skewness and kurtosis, for both ΛCDM and two leading MG models: f(R) gravity and the DGP braneworld model. The ST model reproduces the velocity PDF and redshift-space halo clustering measured from MG N-body simulations very well down to ~5 h^-1Mpc. In particular, we investigate the enhancements of halo pairwise velocity moments with respect to ΛCDM for a larger range of MG variants than previous works, and present simple explanations to the behaviours observed. By performing a simple Fisher analysis, we find a significnat increase in constraining power to detect modifications of General Relativity by introducing small-scale information in the RSD analyses.

We present the first results with the ROentgen Survey with an Imaging Telescope Array (eROSITA) on board the Russian Spektrum-Roentgen-Gamma mission, and we combine the new X-ray data with observations with the Transiting Exoplanet Survey Satellite (TESS). We used the SUPERBLINK proper motion catalog of nearby M dwarfs as input sample to search for eROSITA and TESS data. We extracted Gaia DR2 data for the full M dwarf catalog, which comprises ~9000 stars, and we calculated the stellar parameters from empirical relations with optical/IR colors. Then we cross-matched this catalog with the eROSITA Final Equatorial Depth Survey (eFEDS) and the first eROSITA all-sky survey (eRASS1). After a meticulous source identification in which we associated the closest Gaia source with the eROSITA X-ray detections, our sample of M dwarfs is defined by 687 stars with SpT = K5..M7 (673 from eRASS1 and 14 from eFEDS). While for eRASSl we used the data from the source catalog provided by the eROSITA_DE consortium, for the much smaller eFEDS sample, we performed the data extraction, and we analyzed the X-ray spectra and light curves. This unprecedented data base for X-ray emitting M dwarfs allowed us to place a quantitative constraint on the mass dependence of the X-ray luminosity, and to determine the change in the activity level with respect to pre-main-sequence stars. TESS observations are available for 489 of 687 X-ray detected M dwarfs. By applying standard period search methods, we were able to determine the rotation period for 180 X-ray detected M dwarfs. This is about one-forth of the X-ray sample. With the joint eROSITA and TESS sample, and combining it with our compilation of historical X-ray and rotation data for M dwarfs, we examined the mass dependence of the saturated regime of the rotation-activity relation. A first comparison of eROSITA hardness ratios and spectra shows that 65% of the X-ray detected M dwarfs have coronal temperatures of ~0.5 keV. We performed a statistical investigation of the long-term X-ray variability of M dwarfs by comparing the eROSITA measurements to those obtained ~30 yr earlier during the ROSAT all-sky survey (RASS). Evidence for X-ray flares is found in various parts of our analysis: directly from an inspection of the eFEDS light curves, in the relation between RASS and eRASSl X-ray luminosities, and in a subset of stars that displays hotter X-ray emission than the bulk of the sample according to the hardness ratios. Finally, we point out the need to obtain X-ray spectroscopy for more M dwarfs to study the coronal temperature-luminosity relation, which is not well constrained by our eFEDS results.

Full Tables 2, 3 and 5 are only available at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/661/A29

Recent subarcsecond resolution surveys of the dust continuum emission from nearby protoplanetary disks show a strong correlation between the sizes and luminosities of the disks. We aim to explain the origin of the (sub-)millimeter size-luminosity relation (SLR) between the 68% effective radius (r_eff) of disks with their continuum luminosity (L_mm), with models of gas and dust evolution in a simple viscous accretion disk and radiative transfer calculations. We use a large grid of models (10⁵ simulations) with and without planetary gaps, and vary the initial conditions of the key parameters. We calculate the disk continuum emission and the effective radius for all models as a function of time. By selecting those simulations that continuously follow the SLR, we can derive constraints on the input parameters of the models. We confirm previous results that models of smooth disks in the radial drift regime are compatible with the observed SLR (L_mm ∝ r_eff²), but only smooth disks cannot be the reality. We show that the SLR is more widely populated if planets are present. However, they tend to follow a different relation than smooth disks, potentially implying that a mixture of smooth and substructured disks are present in the observed sample. We derive a SLR (L_mm ∝ r_eff^5/4) for disks with strong substructure. To be compatible with the SLR, models need to have an initially high disk mass (≥2.5 × 10⁻² M_*) and low turbulence-parameter a values (≤10⁻³). Furthermore, we find that the grain composition and porosity drastically affects the evolution of disks in the size-luminosity diagram where relatively compact grains that include amorphous carbon are favored. Moreover, a uniformly optically thick disk with high albedo (0.9) that follows the SLR cannot be formed from an evolutionary procedure.

While protoplanetary disks are often treated as isolated systems in planet formation models, observations increasingly suggest that vigorous interactions between Class II disks and their environments are not rare. DO Tau is a T Tauri star that has previously been hypothesized to have undergone a close encounter with the HV Tau system. As part of the DESTINYS ESO Large Programme, we present new Very Large Telescope (VLT)/SPHERE polarimetric observations of DO Tau and combine them with archival Hubble Space Telescope (HST) scattered-light images and Atacama Large Millimeter/submillimeter Array (ALMA) observations of CO isotopologues and CS to map a network of complex structures. The SPHERE and ALMA observations show that the circumstellar disk is connected to arms extending out to several hundred astronomical units. HST and ALMA also reveal stream-like structures northeast of DO Tau, some of which are at least several thousand astronomical units long. These streams appear not to be gravitationally bound to DO Tau, and comparisons with previous Herschel far-IR observations suggest that the streams are part of a bridge-like structure connecting DO Tau and HV Tau. We also detect a fainter redshifted counterpart to a previously known blueshifted CO outflow. While some of DO Tau's complex structures could be attributed to a recent disk-disk encounter, they might be explained alternatively by interactions with remnant material from the star formation process. These panchromatic observations of DO Tau highlight the need to contextualize the evolution of Class II disks by examining processes occurring over a wide range of size scales.

Context. In November 2019, eROSITA on board of the Spektrum-Roentgen-Gamma (SRG) observatory started to map the entire sky in X-rays. After the four-year survey program, it will reach a flux limit that is about 25 times deeper than ROSAT. During the SRG performance verification phase, eROSITA observed a contiguous 140 deg² area of the sky down to the final depth of the eROSITA all-sky survey (eROSITA Final Equatorial-Depth Survey; eFEDS), with the goal of obtaining a census of the X-ray emitting populations (stars, compact objects, galaxies, clusters of galaxies, and active galactic nuclei) that will be discovered over the entire sky.
Aims: This paper presents the identification of the counterparts to the point sources detected in eFEDS in the main and hard samples and their multi-wavelength properties, including redshift.
Methods: To identifyy the counterparts, we combined the results from two independent methods (NWAY and ASTROMATCH), trained on the multi-wavelength properties of a sample of 23k XMM-Newton sources detected in the DESI Legacy Imaging Survey DR8. Then spectroscopic redshifts and photometry from ancillary surveys were collated to compute photometric redshifts.
Results: Of the eFEDS sources, 24 774 of 27 369 have reliable counterparts (90.5%) in the main sample and 231 of 246 sourcess (93.9%) have counterparts in the hard sample, including 2514 (3) sources for which a second counterpart is equally likely. By means of reliable spectra, Gaia parallaxes, and/or multi-wavelength properties, we have classified the reliable counterparts in both samples into Galactic (2695) and extragalactic sources (22 079). For about 340 of the extragalactic sources, we cannot rule out the possibility that they are unresolved clusters or belong to clusters. Inspection of the distributions of the X-ray sources in various optical/IR colour-magnitude spaces reveal a rich variety of diverse classes of objects. The photometric redshifts are most reliable within the KiDS/VIKING area, where deep near-infrared data are also available.
Conclusions: This paper accompanies the eROSITA early data release of all the observations performed during the performance and verification phase. Together with the catalogues of primary and secondary counterparts to the main and hard samples of the eFEDS survey, this paper releases their multi-wavelength properties and redshifts.

The data are only available at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/661/A3

Context. In 2019, the eROSITA telescope on board the Russian-German satellite Spectrum-Roentgen-Gamma (SRG) began to perform a deep all-sky X-ray survey with the aim of identifying ~100 000 clusters and groups over the course of four years. As part of its performance verification phase, a ~140 deg² survey, called eROSITA Final Equatorial-Depth Survey (eFEDS), was performed. With a depth typical of the all-sky survey after four years, it allows tests of tools and methods as well as improved predictions for the all-sky survey.
Aims: As part of this effort, a catalog of 542 X-ray selected galaxy group and cluster candidates was compiled. In this paper we present the optical follow-up, with the aim of providing redshifts and cluster confirmation for the full sample. Furthermore, we aim to provide additional information on the dynamical state, richness, and optical center of the clusters. Finally, we aim to evaluate the impact of optical cluster confirmation on the purity and completeness of the X-ray selected sample.
Methods: We used optical imaging data from the Hyper Suprime-Cam Subaru Strategic Program and from the Legacy Survey to identify optical counterparts to the X-ray detected cluster candidates. We make use of the multi-component matched filter cluster confirmation tool (MCMF), as well as of the optical cluster finder CAMIRA to derive cluster redshifts and richnesses. MCMF provided the probabilities with which an optical structure would be a chance superposition with the X-ray candidate. These probabilities were used to identify the best optical counterpart as well as to confirm an X-ray candidate as a cluster. The impact of this confirmation process on catalog purity and completeness was estimated using optical to X-ray scaling relations as well as simulations. The resulting catalog was furthermore matched with public group and cluster catalogs. Optical estimators of the cluster dynamical state were constructed based on density maps of the red-sequence galaxies at the cluster redshift.
Results: By providing redshift estimates for all 542 candidates, we construct an optically confirmed sample of 477 clusters and groups with a residual contamination of 6%. Of these, 470 (98.5%) are confirmed using MCMF, and 7 systems are added through cross-matching with spectroscopic group catalogs. Using observable-to-observable scaling and the applied confirmation threshold, we predict that 8 ± 2 real systems have been excluded with the MCMF cut required to build this low-contamination sample. This number agrees well with the 7 systems found through cross-matching that were not confirmed with MCMF. The predicted redshift and mass distribution of this catalog agree well with simulations. Thus, we expect that these 477 systems include >99% of all true clusters in the candidate list. Using an MCMF-independent method, we confirm that the catalog contamination of the confirmed subsample is 6 ± 3%. Application of the same method to the full candidate list yields 17 ± 3%, consistent with estimates coming from the fraction of confirmed systems of ~17% and with expectations from simulations of ~20%. We also present a sample of merging cluster candidates based on the derived estimators of the cluster dynamical state.

The catalog is only available at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/661/A4

We present a fast and precise method to approximate the physics model of the Karlsruhe Tritium Neutrino (KATRIN) experiment using a neural network. KATRIN is designed to measure the effective electron anti-neutrino mass m_ν using the kinematics of β -decay with a sensitivity of 200 meV at 90% confidence level. To achieve this goal, a highly accurate model prediction with relative errors below the 10^-4-level is required. Using the regular numerical model for the analysis of the final KATRIN dataset is computationally extremely costly or requires approximations to decrease the computation time. Our solution to reduce the computational requirements is to train a neural network to learn the predicted β -spectrum and its dependence on all relevant input parameters. This results in a speed-up of the calculation by about three orders of magnitude, while meeting the stringent accuracy requirements of KATRIN.

Ultra-hot Jupiters (UHJs) are expected to possess temperature inversion layers in their dayside atmospheres. Recent thermal emission observations have discovered several atomic and molecular species along with temperature inversions in UHJs. We observed the thermal emission spectra of two UHJs (WASP-33b and WASP-189b) with the GIANO-B high-resolution near-infrared spectrograph. Using the cross-correlation technique, we detected carbon monoxide (CO) in the dayside atmospheres of both planets. The detected CO lines are in emission, which agrees with previous discoveries of iron emission lines and temperature inversions in the two planets. This is the first detection of CO lines in emission with high-resolution spectroscopy. Further retrieval work combining the CO lines with other spectral features will enable a comprehensive understanding of the atmospheric properties such as temperature structures and C/O ratios. The detected CO and iron emission lines of WASP-189b have redshifted radial velocities of several km s⁻¹, which likely originate from a dayside to nightside wind in its atmosphere. Such a redshifted velocity has not been detected for the emission lines of WASP-33b, suggesting that the atmospheric circulation patterns of the two UHJs may be different.

Context. Clusters of galaxies reside at the nodes of the cosmic web, interconnected by filamentary structures that contain tenuous diffuse gas, especially in the warm-hot phase. Galaxy clusters grow by mergers of smaller objects and gas that are mainly accreted through these large-scale filaments. For the first time, the large-scale cosmic structure and a long gas-emission filament have been captured by eROSITA on board the Spectrum-Roentgen-Gamma mission in a direct X-ray observation of the A3391/95 field.
Aims: We investigate the assembly history of an A3391/95-like system of clusters and the thermo-chemical properties of the diffuse gas in it by connecting simulation predictions to the eROSITA observations with the aim to constrain the origin and nature of the gas in the pair-interconnecting bridge.
Methods: We analysed the properties of a system resembling A3391/95, extracted from the (352 h⁻¹ cMpc)³ volume of the Magneticum Pathfinder cosmological simulations at z = 0.07. We tracked the main progenitors of the pair clusters and of surrounding groups back in time to study the assembly history of the system and its evolution.
Results: Similarly to the observed A3391/95 system, the simulated cluster pair is embedded in a complex network of gas filaments, with structures aligned over more than 20 projected Mpc, and the whole region collapses towards the central overdense node. The spheres of influence (3 × R₂₀₀) of the two main clusters already overlap at z = 0.07, but their virial boundaries are still physically separated. The diffuse gas located in the interconnecting bridge closely reflects the warm-hot intergalactic medium, with a typical temperature of ~1 keV and an overdensity δ ~ 100 with respect to the mean baryon density of the Universe, and a lower enrichment level compared to the intra-cluster medium in clusters. We find that most of the bridge gas collapsed from directions roughly orthogonal to the intra-cluster gas accretion directions, and its origin is mostly unrelated to the two cluster progenitors. We find clear signatures in the surrounding groups of infall motion towards the pair, such as significant radial velocities and a slowdown of gas compared to dark matter. These findings further support the hypothesis that the Northern Clump (MCXC J0621.7-5242) cluster infalls along a cosmic gas filament towards Abell 3391 and might be merging with it.
Conclusions: We conclude that in this configuration, the pair clusters of the A3391/95-like system are in a pre-merger phase and have not yet interacted. The diffuse gas in the interconnecting bridge is mostly warm filament gas and not tidally stripped cluster gas.

The observed pattern of linear polarization of the cosmic microwave background (CMB) photons is a sensitive probe of physics violating parity symmetry under inversion of spatial coordinates. A new parity-violating interaction might have rotated the plane of linear polarization by an angle $\beta$ as the CMB photons have been traveling for more than 13 billion years. This effect is known as ''cosmic birefringence.'' In this paper, we present new measurements of cosmic birefringence from a joint analysis of polarization data from two space missions, Planck and WMAP. This dataset covers a wide range of frequencies from 23 to 353 GHz. We measure $\beta = 0.342^{\circ\,+0.094^\circ}_{\phantom{\circ\,}-0.091^\circ}$ (68% C.L.) for nearly full-sky data, which excludes $\beta=0$ at 99.987% C.L. This corresponds to the statistical significance of $3.6\sigma$. There is no evidence for frequency dependence of $\beta$. We find a similar result, albeit with a larger uncertainty, when removing the Galactic plane from the analysis.

The lack of convergence of the convolution integrals appearing in next-to-leading-power (NLP) factorization theorems prevents the applications of existing methods to resum power-suppressed large logarithmic corrections in collider physics. We consider thrust distribution in the two-jet region for the flavour-nonsinglet off-diagonal contribution, where a gluon-initiated jet recoils against a quark-antiquark pair, which is power-suppressed. With the help of operatorial endpoint factorization conditions, we obtain a factorization formula, where the individual terms are free from endpoint divergences in convolutions and can be expressed in terms of renormalized hard, soft and collinear functions in four dimensions. This allows us to perform the first resummation of the endpoint-divergent SCET$_{\rm I}$ observables at the leading logarithmic accuracy using exclusively renormalization-group methods. The presented approach relies on universal properties of the soft and collinear limits and may serve as a paradigm for the systematic NLP resummation for other $1\to 2$ and $2\to 1$ collider physics processes.

Using synthetic Lyman-$\alpha$ forests from the Dark Energy Spectroscopic Instrument (DESI) survey, we present a study of the impact of errors in the estimation of quasar redshift on the Lyman-$\alpha$ correlation functions. Estimates of quasar redshift have large uncertainties of a few hundred $\text{km s}^{-1}\,$ due to the broadness of the emission lines and the intrinsic shifts from other emission lines. We inject Gaussian random redshift errors into the mock quasar catalogues, and measure the auto-correlation and the Lyman-$\alpha$-quasar cross-correlation functions. We find a smearing of the BAO feature in the radial direction, but changes in the peak position are negligible. However, we see a significant unphysical correlation for small separations transverse to the line of sight which increases with the amplitude of the redshift errors. We interpret this contamination as a result of the broadening of emission lines in the measured mean continuum, caused by quasar redshift errors, combined with the unrealistically strong clustering of the simulated quasars on small scales.

Axion-gluon interaction induces quadratic couplings between the axion and the matter fields. We find that, if the axion is an ultralight dark matter field, it induces small oscillations of the mass of the hadrons as well as other nuclear quantities. As a result, atomic energy levels oscillate. We use currently available atomic spectroscopy data to constrain such axion-gluon coupling. We also project the sensitivities of future experiments, such as ones using molecular and nuclear clock transitions. We show that current and near-future experiments constrain a finely-tuned parameter space of axion models. These can compete or dominate the already-existing constraints from oscillating neutron electric dipole moment and supernova bound, in addition to those expected from near future magnetometer-based experiments.

We investigate the ten independent local form-factors relevant to the $b$-baryon decay $\Lambda_b \to \Lambda \ell^+\ell^-$, combining information of lattice QCD and dispersive bounds. We propose a novel parametrization of the form factors in terms of orthonormal polynomials that diagonalizes the form factor contributions to the dispersive bounds. This is a generalization of the unitarity bounds developed for meson-to-meson form-factors. In contrast to ad-hoc parametrizations of these form factors, our parametrization provides a degree of control of the form-factor uncertainties at large hadronic recoil. This is of phenomenological interest for theoretical predictions of, e.g., $\Lambda_b\to \Lambda \gamma$ and $\Lambda_b\to\Lambda \ell^+\ell^-$ decay processes.

Aims: The eROSITA Final Equatorial-Depth Survey (eFEDS), executed during the performance verification phase of the Spectrum-Roentgen-Gamma (SRG)/eROSITA telescope, was completed in November 2019. One of the science goals of this survey is to demonstrate the ability of eROSITA to detect samples of clusters and groups at the final depth of the eROSITA all-sky survey.
Methods: Because of the sizeable (≈26″ HEW FOV average) point-spread function of eROSITA, high-redshift clusters of galaxies or compact nearby groups hosting bright active galactic nuclei (AGN) can be misclassified as point sources by the source detection algorithms. A total of 346 galaxy clusters and groups in the redshift range of 0.1 < z < 1.3 were identified based on their red sequenc in the eFEDS point source catalog.
Results: We examine the multiwavelength properties of these clusters and groups to understand the potential biases in our selection process and the completeness of the extent-selected sample. We find that the majority of the clusters and groups in the point source sample are indeed underluminous and compact compared to the extent-selected sample. Their faint X-ray emission, well below the flux limit of the extent-selected eFEDS clusters, and their compact X-ray emission are likely to be the main reason for this misclassification. In the sample, we confirm that 10% of the sources host AGN in their brightest cluster galaxies (BCGs) through optical spectroscopy and visual inspection. By studying their X-ray, optical, infrared, and radio properties, we establish a method for identifying clusters and groups that host AGN in their BCGs. We successfully test this method on the current point source catalog through the Sloan Digital Sky Survey optical spectroscopy and find eight low-mass clusters and groups with active radio-loud AGN that are particularly bright in the infrared. They include eFEDS J091437.8+024558, eFEDS J083520.1+012516, and eFEDS J092227.1+043339 at redshifts 0.3−0.4.
Conclusions: This study helps us to characterize and understand our selection process and assess the completeness of the eROSITA extent-selected samples. The method we developed will be used to identify high-redshift clusters, AGN-dominated groups, and low-mass clusters that are misclassified in the future eROSITA all-sky survey point source catalogs.

Table 3 is only available at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/661/A10

Context. Red supergiant (RSGs) are cool massive stars in a late phase of their evolution when the stellar envelope becomes fully convective. They are the brightest stars in the universe at infrared light and can be detected in galaxies far beyond the Local Group, allowing for accurate determination of chemical composition of galaxies. The study of their physical properties is extremely important for various phenomena including the final fate of massive stars as type II supernovae and gravitational wave progenitors.
Aims: We explore the well-studied nearby young stellar cluster χ Per, which contains a relatively large population of RSG stars. Using Gaia EDR3 data, we find the distance of the cluster (d = 2.260 ± 0.020 kpc) from blue main sequence stars and compare with RSG parallax measurements analysing the parallax uncertainties of both groups. We then investigate the variability of the convection-related surface structure as a source for parallax measurement uncertainty.
Methods: We use state-of-the-art three-dimensional radiative hydrodynamics simulations of convection with CO5BOLD and the post-processing radiative transfer code OPTIM3D to compute intensity maps in the Gaia G photometric system. We calculate the variabiltiy, as a function of time, of the intensity-weighted mean (or the photo-center) from the synthetic maps. We then select the RSG stars in the cluster and compare their uncertainty on parallaxes to the predictions of photocentre displacements.
Results: The synthetic maps of RSG show extremely irregular and temporal variable surfaces due to convection-related dynamics. Consequentially, the position of the photo-center varies during Gaia measurements between 0.033 and 0.130 AU (≈1 to ≈5% of the corresponding simulation stellar radius). We argue that the variability of the convection-related surface structures accounts for a substantial part of the Gaia EDR3 parallax error of the RSG sample of χ Per.
Conclusions: We suggest that the variation of the uncertainty on Gaia parallax could be exploited quantitatively using appropriate RHD simulations to extract, in a unique way, important information about the stellar dynamics and parameters of RSG stars.

Movies are available at https://www.aanda.org

Theoretical models of the co-evolution of galaxies and active galactic nuclei (AGNs) ascribe an important role in the feedback process to a short, luminous, obscured, and dust-enshrouded phase during which the accretion rate of the supermassive black hole is expected to be at its maximum and the associated AGN-driven winds are also predicted to be maximally developed. To test this scenario, we have isolated a textbook candidate from the eROSITA Final Equatorial-Depth Survey (eFEDS) obtained within the performance and verification program of the eROSITA telescope on board the Spectrum Röntgen Gamma mission. From an initial catalogue of 246 hard X-ray selected sources that are matched with the photometric and spectroscopic information available within the eROSITA and Hyper Suprime-Cam consortia, three candidates quasars in the feedback phase have been isolated applying a diagnostic proposed previously. Only one source (eFEDS J091157.4+014327) has a spectrum already available (from SDSS-DR16, z = 0.603) and it unambiguously shows abroad component (full width at half maximum ~1650 kms⁻¹) in the [OIII]5007 line. The associated observed L_[OIII] is ~2.6 × 10⁴² erg s⁻¹, one to two orders of magnitude higher than that observed in local Seyfert galaxies and comparable to those observed in a sample of z ~ 0.5 type 1 quasars. From the multi-wavelength data available, we derive an Eddington ratio (L_bol/L_Edd) of ~0.25 and a bolometric correction in the hard X-ray band of k_bol ~ 10, which is lower than the corrections observed for objects at similar bolometric luminosity. These properties, along with the outflow, the high X-ray luminosity, the moderate X-ray obscuration (L_X∽10^44.8 erg s⁻¹, N_H∽2.7 × 10²² cm⁻²), and the red optical colour, all match the prediction of quasars in the feedback phase from merger-driven models. Forecasting to the full eROSITA all-sky survey with its spectroscopic follow-up, we predict that by the end of 2024, we will have a sample of few hundred such objects at z= 0.5-2.

The Dark Energy Spectroscopic Instrument (DESI) has embarked on an ambitious five-year survey to explore the nature of dark energy with spectroscopy of 40 million galaxies and quasars. DESI will determine precise redshifts and employ the Baryon Acoustic Oscillation method to measure distances from the nearby universe to z > 3.5, as well as measure the growth of structure and probe potential modifications to general relativity. In this paper we describe the significant instrumentation we developed for the DESI survey. The new instrumentation includes a wide-field, 3.2-deg diameter prime-focus corrector that focuses the light onto 5020 robotic fiber positioners on the 0.812 m diameter, aspheric focal surface. The positioners and their fibers are divided among ten wedge-shaped petals. Each petal is connected to one of ten spectrographs via a contiguous, high-efficiency, nearly 50 m fiber cable bundle. The ten spectrographs each use a pair of dichroics to split the light into three channels that together record the light from 360 - 980 nm with a resolution of 2000 to 5000. We describe the science requirements, technical requirements on the instrumentation, and management of the project. DESI was installed at the 4-m Mayall telescope at Kitt Peak, and we also describe the facility upgrades to prepare for DESI and the installation and functional verification process. DESI has achieved all of its performance goals, and the DESI survey began in May 2021. Some performance highlights include RMS positioner accuracy better than 0.1", SNR per √(Å) > 0.5 for a z > 2 quasar with flux 0.28e-17 erg/s/cm^2/A at 380 nm in 4000s, and median SNR = 7 of the [OII] doublet at 8e-17 erg/s/cm^2 in a 1000s exposure for emission line galaxies at z = 1.4 - 1.6. We conclude with highlights from the on-sky validation and commissioning of the instrument, key successes, and lessons learned. (abridged)

Negative feedback from active galactic nuclei (AGN) is the leading mechanism for the quenching of massive galaxies in the vast majority of modern galaxy evolution models. However, direct observational evidence that AGN feedback causes quenching on a population scale is lacking. Studies have shown that luminous AGN are preferentially located in gas-rich and star-forming galaxies, an observation that has sometimes been suggested to be in tension with a negative AGN feedback picture. We investigate three of the current cosmological simulations (IllustrisTNG, EAGLE and SIMBA) along with post-processed models for molecular hydrogen gas masses and perform similar tests to those used by observers. We find that the simulations predict: (i) no strong negative trends between AGN luminosity and molecular gas fraction or sSFR; (ii) both high-luminosity ($L_{bol}>10^{44}$ erg/s) and high-Eddington ratio (>1%) AGN are preferentially located in galaxies with high molecular gas fractions and sSFR; and (iii) that the gas-depleted and quenched fractions of AGN host galaxies are lower than a control sample of non-active galaxies. These three findings are in qualitative agreement with observational samples at $z=0$ and $z=2$ and show that such results are not in tension with the presence of strong AGN feedback, which all simulations we employ require to produce realistic massive galaxies. However, we also find quantifiable differences between predictions from the simulations, which could allow us to observationally test the different subgrid feedback models.

Photoevaporative winds are a promising mechanism for dispersing protoplanetary discs, but so far theoretical models have been unable to agree on the relative roles that the X-ray, Extreme Ultraviolet or Far Ultraviolet play in driving the winds. This has been attributed to a variety of methodological differences between studies, including their approach to radiative transfer and thermal balance, the choice of irradiating spectrum employed, and the processes available to cool the gas. We use the \textsc{mocassin} radiative transfer code to simulate wind heating for a variety of spectra on a static density grid taken from simulations of an EUV-driven wind. We explore the impact of choosing a single representative X-ray frequency on their ability to drive a wind by measuring the maximum heated column as a function of photon energy. We demonstrate that for reasonable luminosities and spectra, the most effective energies are at a few $100~\mathrm{eV}$, firmly in the softer regions of the X-ray spectrum, while X-rays with energies $\sim1000~\mathrm{eV}$ interact too weakly with disc gas to provide sufficient heating to drive a wind. We develop a simple model to explain these findings. We argue that further increases in the cooling above our models - for example due to molecular rovibrational lines - may further restrict the heating to the softer energies but are unlikely to prevent X-ray heated winds from launching entirely; increasing the X-ray luminosity has the opposite effect. The various results of photoevaporative wind models should therefore be understood in terms of the choice of irradiating spectrum.

We model here the merger histories of the supermassive black hole (SMBH) population in the late stages of a cosmological simulation of a ~ 2 × 10¹³ M _⊙ galaxy group. The gravitational dynamics around the several tens of SMBHs (M _• > 7.5 × 10⁷ M _⊙) hosted by the galaxies in the group is computed at high accuracy using regularized integration with the KETJU code. The 11 SMBHs that form binaries and a hierarchical triplet eventually merge after hardening through dynamical friction, stellar scattering, and gravitational wave (GW) emission. The binaries form at eccentricities of e ~ 0.3-0.9, with one system evolving to a very high eccentricity of e = 0.998, and merge on timescales of a few tens to several hundred megayears. During the simulation, the merger-induced GW recoil kicks eject one SMBH remnant from the central host galaxy. This temporarily drives the galaxy off the M _•-σ _⋆ relation; however, the galaxy returns to the relation due to subsequent galaxy mergers, which bring in new SMBHs. This showcases a possible mechanism contributing to the observed scatter of the M _•-σ _⋆ relation. Finally, we show that pulsar timing arrays and LISA would be able to detect parts of the GW signals from the SMBH mergers that occur during the ~4 Gyr time span simulated with KETJU.

In this work we study possible connections between B-meson anomalies and Kaon physics observables in the context of combined solutions with the singlet and triplet scalar leptoquarks S₁ and S₃. By assuming a flavor structure for the leptoquark couplings dictated by a minimally broken U (2^{) 5} flavor symmetry we can make a sharp connection between these two classes of observables. We find that the bound on B (K⁺→π⁺ν ν ) from NA62 puts already some tension in the model, while the present limits on B (K_L→μ⁺μ^-) and μ →e conversion in nuclei can be saturated. Relaxing instead the flavor assumption we study what values for B (K⁺→π⁺ν ν ) , as well as for B (K_L→π⁰ν ν ) and B (K_{L ,S}→μ⁺μ^-) , are viable compatibly with all other phenomenological constraints.

We present spectroscopic measurements for 71 galaxies associated with 62 of the brightest high-redshift submillimetre sources from the Southern fields of the Herschel Astrophysical Terahertz Large Area Survey (H-ATLAS), while targeting 85 sources which resolved into 142. We have obtained robust redshift measurements for all sources using the 12-m Array and an efficient tuning of ALMA to optimize its use as a redshift hunter, with 73 per cent of the sources having a robust redshift identification. Nine of these redshift identifications also rely on observations from the Atacama Compact Array. The spectroscopic redshifts span a range 1.41 < z < 4.53 with a mean value of 2.75, and the CO emission line full-width at half-maxima range between $\rm 110\, km\, s^{-1} \lt FWHM \lt 1290\, km\, s^{-1}$ with a mean value of ~500 km s^-1, in line with other high-z samples. The derived CO(1-0) luminosity is significantly elevated relative to line-width to CO(1-0) luminosity scaling relation, which is suggestive of lensing magnification across our sources. In fact, the distribution of magnification factors inferred from the CO equivalent widths is consistent with expectations from galaxy-galaxy lensing models, though there is a hint of an excess at large magnifications that may be attributable to the additional lensing optical depth from galaxy groups or clusters.

In this work we examine the impact of our motion with respect to the CMB rest frame on statistics of CMB maps by examining the one-, two-, three- and four- point statistics of simulated maps of the CMB and Sunyaev-Zeldovich (SZ) effects. We validate boosting codes by comparing their outcomes for temperature and polarization power spectra up to ℓ ≃ 6000. We derive and validate a new analytical formula for the computation of the boosted power spectrum of a signal with a generic frequency dependence. As an example we show how this increases the boosting correction to the power spectrum of CMB intensity measurements by $\sim 30{\rm{ per\ cent}}$ at 150 GHz. We examine the effect of boosting on thermal and kinetic SZ power spectra from semianalytical and hydrodynamical simulations; the boosting correction is generally small for both simulations, except when considering frequencies near the tSZ null. For the non-Gaussian statistics, in general we find that boosting has no impact with two exceptions. We find that, whilst the statistics of the CMB convergence field are unaffected, quadratic estimators that are used to measure this field can become biased at the $O(1){\rm{ per\ cent}}$ level by boosting effects. We present a simple modification to the standard estimators that removes this bias. Second, bispectrum estimators can receive a systematic bias from the Doppler induced quadrupole when there is anisotropy in the sky - in practice this anisotropy comes from masking and inhomegenous noise. This effect is unobservable and already removed by existing analysis methods.

Photoevaporative winds are a promising mechanism for dispersing protoplanetary discs, but so far theoretical models have been unable to agree on the relative roles that the X-ray, Extreme Ultraviolet or Far Ultraviolet play in driving the winds. This has been attributed to a variety of methodological differences between studies, including their approach to radiative transfer and thermal balance, the choice of irradiating spectrum employed, and the processes available to cool the gas. We use the MOCASSIN radiative transfer code to simulate wind heating for a variety of spectra on a static density grid taken from simulations of an EUV-driven wind. We explore the impact of choosing a single representative X-ray frequency on their ability to drive a wind by measuring the maximum heated column as a function of photon energy. We demonstrate that for reasonable luminosities and spectra, the most effective energies are at a few 100 eV, firmly in the softer regions of the X-ray spectrum, while X-rays with energies ~1000 eV interact too weakly with disc gas to provide sufficient heating to drive a wind. We develop a simple model to explain these findings. We argue that further increases in the cooling above our models - for example due to molecular rovibrational lines - may further restrict the heating to the softer energies but are unlikely to prevent X-ray heated winds from launching entirely; increasing the X-ray luminosity has the opposite effect. The various results of photoevaporative wind models should therefore be understood in terms of the choice of irradiating spectrum.

We present the median-stacked Lyman-α (Lyα) surface brightness profiles of 968 spectroscopically selected Lyα emitting galaxies (LAEs) at redshifts 1.9 < z < 3.5 in the early data of the Hobby-Eberly Telescope Dark Energy Experiment. The selected LAEs are high-confidence Lyα detections with high signal-to-noise ratios observed with good seeing conditions (point-spread function FWHM <1.″4), excluding active galactic nuclei. The Lyα luminosities of the LAEs are 10^42.4-10⁴³ erg s^-1. We detect faint emission in the median-stacked radial profiles at the level of <?CDATA $(3.6\pm 1.3)\times {10}^{-20}\,\mathrm{erg}\,{{\rm{s}}}^{-1}\,{\mathrm{cm}}^{-2}\,{\mathrm{arcsec}}^{-2}$?> from the surrounding Lyα halos out to r ≃ 160 kpc (physical). The shape of the median-stacked radial profile is consistent at r < 80 kpc with that of much fainter LAEs at 3 < z < 4 observed with the Multi Unit Spectroscopic Explorer (MUSE), indicating that the median-stacked Lyα profiles have similar shapes at redshifts 2 < z < 4 and across a factor of 10 in Lyα luminosity. While we agree with the results from the MUSE sample at r < 80 kpc, we extend the profile over a factor of two in radius. At r > 80 kpc, our profile is flatter than the MUSE model. The measured profile agrees at most radii with that of galaxies in the Byrohl et al. cosmological radiative transfer simulation at z = 3. This suggests that the surface brightness of a Lyα halo at r ≲ 100 kpc is dominated by resonant scattering of Lyα photons from star-forming regions in the central galaxy, whereas at r > 100 kpc, it is dominated by photons from galaxies in surrounding dark matter halos.

We study the evolution of dust in a cosmological volume using a hydrodynamical simulation in which the dust production is coupled with the MUPPI (MUlti Phase Particle Integrator) sub-resolution model of star formation and feedback. As for the latter, we keep as reference the model setup calibrated previously to match the general properties of Milky Way like galaxies in zoom-in simulations. However, we suggest that an increase of the star formation efficiency with the local dust to gas ratio would better reproduce the observed evolution of the cosmic star formation density. Moreover, the paucity of quenched galaxies at low redshift demands a stronger role of AGN feedback. We tune the parameters ruling direct dust production from evolved stars and accretion in the inter stellar medium to get scaling relations involving dust, stellar mass and metallicity in good agreement with observations. In low mass galaxies the accretion process is inefficient. As a consequence, they remain poorer in silicate and small grains than higher mass ones. We reproduce reasonably well the few available data on the radial distribution of dust outside the galactic region, supporting the assumption that the dust and gas dynamics are well coupled at galactic scales.

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 $q\bar q$ 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 molecules and comment on a possible charmless component of the $XYZ$ states.

We perform two distinct spatio-spectral reconstructions of the gamma-ray sky in the range of 0.56-316 GeV based on Fermi Large Area Telescope (LAT) data. Both describe the sky brightness to be composed of a diffuse-emission and a point-source component. The first model requires minimal assumptions and provides a template-free reconstruction as a reference. It makes use of spatial and spectral correlations to distinguish between the different components. The second model is physics-informed and further differentiates between diffuse emission of hadronic and leptonic origin. For this, we assume parametric, but spatially varying energy spectra to distinguish between the processes and use thermal Galactic dust observations to indicate the preferred sites of hadronic interactions. To account for instrumental effects we model the point-spread, the energy dispersion, and the exposure of the telescope throughout the observation. The reconstruction problem is formulated as a Bayesian inference task, that is solved by variational inference. We show decompositions of the Gamma-ray flux into diffuse and point-like emissions, and of the diffuse emissions into multiple physically motivated components. The diffuse decomposition provides an unprecedented view of the Galactic leptonic diffuse emission. It shows the Fermi bubbles and their spectral variations in high fidelity and other areas exhibiting strong cosmic ray electron contents, such as a thick disk in the inner Galaxy and outflow regions. Furthermore, we report a hard spectrum gamma ray arc in the northern outer bubble co-spatial with the reported X-ray arc by the eROSITA collaboration. All our spatio-spectral sky reconstructions and their uncertainty quantification are publicly available.

Gravitationally lensed supernovae (LSNe) are important probes of cosmic expansion, but they remain rare and difficult to find. Current cosmic surveys likely contain and 5-10 LSNe in total while next-generation experiments are expected to contain several hundreds to a few thousands of these systems. We search for these systems in observed Dark Energy Survey (DES) 5-year SN fields -- 10 3-sq. deg. regions of sky imaged in the $griz$ bands approximately every six nights over five years. To perform the search, we utilize the DeepZipper approach: a multi-branch deep learning architecture trained on image-level simulations of LSNe that simultaneously learns spatial and temporal relationships from time series of images. We find that our method obtains a LSN recall of 61.13% and a false positive rate of 0.02% on the DES SN field data. DeepZipper selected 2,245 candidates from a magnitude-limited ($m_i$ $<$ 22.5) catalog of 3,459,186 systems. We employ human visual inspection to review systems selected by the network and find three candidate LSNe in the DES SN fields.

The Peak-Patch algorithm is used to identify the densest minicluster seeds in the initial axion density field simulated from string decay. The fate of these dense seeds is found by tracking the subsequent gravitational collapse in cosmological $N$-body simulations. We find that miniclusters at late times are well described by NFW profiles, although for around 80\% of simulated miniclusters a single power-law density profile of $r^{-2.9}$ is an equally good fit due to the unresolved scale radius. Under the assumption that all miniclusters with an unresolved scale radius are described by a power-law plus axion star density profile, we identify a significant number of miniclusters that might be dense enough to give rise to gravitational microlensing if the axion mass is $0.2 \,\mathrm{meV}\lesssim m_a \lesssim 3\,\mathrm{meV}$. Higher resolution simulations resolving the inner structure and axion star formation are necessary to explore this possibility further.

A dark energy-like component in the early universe, known as early dark energy (EDE), is a proposed solution to the Hubble tension. Currently, there is no consensus in the literature as to whether EDE can simultaneously solve the Hubble tension and provide an adequate fit to the data from the cosmic microwave background (CMB) and large-scale structure of the universe. In this work, we deconstruct the current constraints from the Planck CMB and the full-shape clustering data of the Baryon Oscillation Spectroscopic Survey to understand the origin of different conclusions in the literature. We use two different analyses, a grid sampling and a profile likelihood, to investigate whether the current constraints suffer from volume effects upon marginalization and are biased toward some values of the EDE fraction, f _EDE. We find that the f _EDE allowed by the data strongly depends on the particular choice of the other parameters of the model, and that several choices of these parameters prefer larger values of f _EDE than in the Markov Chain Monte Carlo analysis. This suggests that volume effects are the reason behind the disagreement in the literature. Motivated by this, we use a profile likelihood to analyze the EDE model and compute a confidence interval for f _EDE, finding f _EDE = 0.072 ± 0.036 (68% C.L.). Our approach gives a confidence interval that is not subject to volume effects and provides a powerful tool to understand whether EDE is a possible solution to the Hubble tension.

Accurate characterization of the polarized dust emission from our Galaxy will be decisive in the quest for the cosmic microwave background (CMB) primordial B-modes. An incomplete modeling of its potentially complex spectral properties could lead to biases in the CMB polarization analyses and to a spurious measurement of the tensor-to-scalar ratio r. It is particularly crucial for future surveys like the LiteBIRD satellite, the goal of which is to constrain the faint primordial signal leftover by inflation with an accuracy on the tensor-to-scalar ratio r of the order of 10⁻³. Variations of the dust properties along and between lines of sight lead to unavoidable distortions of the spectral energy distribution (SED) that cannot be easily anticipated by standard component-separation methods. This issue can be tackled using a moment expansion of the dust SED, an innovative parametrization method imposing minimal assumptions on the sky complexity. In the present paper, we apply this formalism to the B-mode cross-angular power spectra computed from simulated LiteBIRD polarization data at frequencies between 100 and 402 GHz that contain CMB, dust, and instrumental noise. The spatial variation of the dust spectral parameters (spectral index β and temperature T) in our simulations lead to significant biases on r (∼21 σ_r) if not properly taken into account. Performing the moment expansion in β, as in previous studies, reduces the bias but does not lead to sufficiently reliable estimates of r. We introduce, for the first time, the expansion of the cross-angular power spectra SED in both β and T, showing that, at the sensitivity of LiteBIRD, the SED complexity due to temperature variations needs to be taken into account in order to prevent analysis biases on r. Thanks to this expansion, and despite the existing correlations between some of the dust moments and the CMB signal responsible for a rise in the error on r, we can measure an unbiased value of the tensor-to-scalar ratio with a dispersion as low as σ_r = 8.8 × 10⁻⁴.

We present analytic results for the two tennis-court integral families relevant to 2 → 2 scattering processes involving one massive external particle and massless propagators in terms of Goncharov polylogarithms of up to transcendental weight six. We also present analytic results for physical kinematics for the ladder-box family and the two tennis-court families in terms of real-valued polylogarithmic functions, making our solutions well-suited for phenomenological applications.

Context. At present, there are strong indications that white dwarf (WD) stars with masses well below the Chandrasekhar limit (M_Ch ≈ 1.4 M_⊙) contribute a significant fraction of SN Ia progenitors. The relative fraction of stable iron-group elements synthesized in the explosion has been suggested as a possible discriminant between M_Ch and sub-M_Ch events. In particular, it is thought that the higher-density ejecta of M_Ch WDs, which favours the synthesis of stable isotopes of nickel, results in prominent [Ni II] lines in late-time spectra (≳150 d past explosion).
Aims: We study the explosive nucleosynthesis of stable nickel in SNe Ia resulting from M_Ch and sub-M_Ch progenitors. We explore the potential for lines of [Ni II] in the optical an near-infrared (at 7378 Å and 1.94 μm) in late-time spectra to serve as a diagnostic of the exploding WD mass.
Methods: We reviewed stable Ni yields across a large variety of published SN Ia models. Using 1D M_Ch delayed-detonation and sub-M_Ch detonation models, we studied the synthesis of stable Ni isotopes (in particular, ⁵⁸Ni) and investigated the formation of [Ni II] lines using non-local thermodynamic equilibrium radiative-transfer simulations with the CMFGEN code.
Results: We confirm that stable Ni production is generally more efficient in M_Ch explosions at solar metallicity (typically 0.02-0.08 M_⊙ for the ⁵⁸Ni isotope), but we note that the ⁵⁸Ni yield in sub-M_Ch events systematically exceeds 0.01 M_⊙ for WDs that are more massive than one solar mass. We find that the radiative proton-capture reaction ⁵⁷Co(p, γ)⁵⁸Ni is the dominant production mode for ⁵⁸Ni in both M_Ch and sub-M_Ch models, while the α-capture reaction on ⁵⁴Fe has a negligible impact on the final ⁵⁸Ni yield. More importantly, we demonstrate that the lack of [Ni II] lines in late-time spectra of sub-M_Ch events is not always due to an under-abundance of stable Ni; rather, it results from the higher ionization of Ni in the inner ejecta. Conversely, the strong [Ni II] lines predicted in our 1D M_Ch models are completely suppressed when ⁵⁶Ni is sufficiently mixed with the innermost layers, which are rich in stable iron-group elements.
Conclusions: [Ni II] lines in late-time SN Ia spectra have a complex dependency on the abundance of stable Ni, which limits their use in distinguishing among M_Ch and sub-M_Ch progenitors. However, we argue that a low-luminosity SN Ia displaying strong [Ni II] lines would most likely result from a Chandrasekhar-mass progenitor.

We construct a relativistic chiral nucleon-nucleon interaction up to the next-to-next-to-leading order in covariant baryon chiral perturbation theory. We show that a good description of the n p phase shifts up to T_lab=200 MeV and even higher can be achieved with a χ^{∼ 2}/d .o .f . less than 1. Both the next-to-leading-order results and the next-to-next-to-leading-order results describe the phase shifts equally well up to T_lab=200 MeV , but for higher energies, the latter behaves better, showing satisfactory convergence. The relativistic chiral potential provides the most essential inputs for relativistic ab initio studies of nuclear structure and reactions, which has been in need for almost two decades.

The outflows from neutrino-cooled black hole accretion disks formed in neutron-star mergers or cores of collapsing stars are expected to be neutron-rich enough to explain a large fraction of elements created by the rapid neutron-capture process, but their precise chemical composition remains elusive. Here, we investigate the role of fast neutrino flavor conversion, motivated by the findings of our post-processing analysis that shows evidence of electron-neutrino lepton-number crossings deep inside the disk, hence suggesting possibly nontrivial effects due to neutrino flavor mixing. We implement a parametric, dynamically self-consistent treatment of fast conversion in time-dependent simulations and examine the impact on the disk and its outflows. By activating the otherwise inefficient, emission of heavy-lepton neutrinos, fast conversions enhance the disk cooling rates and reduce the absorption rates of electron-type neutrinos, causing a reduction of the electron fraction in the disk by 0.03-0.06 and in the ejected material by 0.01-0.03. The rapid neutron-capture process yields are enhanced by typically no more than a factor of two, rendering the overall impact of fast conversions modest. The kilonova is prolonged as a net result of increased lanthanide opacities and enhanced radioactive heating rates. We observe only mild sensitivity to the disk mass, the condition for the onset of flavor conversion, and to the considered cases of flavor mixing. Remarkably, parametric models of flavor mixing that conserve the lepton numbers per family result in an overall smaller impact than models invoking three-flavor equipartition, often assumed in previous works.

We explore the effective field theory of a vector field $X^\mu$ that has a Stückelberg mass. The absence of a gauge symmetry for $X^\mu$ implies Lorentz-invariant operators are constructed directly from $X^\mu$. Beyond the kinetic and mass terms, allowed interactions at the renormalizable level include $X_\mu X^\mu H^\dagger H$, $(X_\mu X^\mu)^2$, and $X_\mu j^\mu$, where $j^\mu$ is a global current of the SM or of a hidden sector. We show that all of these interactions lead to scattering amplitudes that grow with powers of $\sqrt{s}/m_X$, except for the case of $X_\mu j^\mu$ where $j^\mu$ is a nonanomalous global current. The latter is well-known when $X$ is identified as a dark photon coupled to the electromagnetic current, often written equivalently as kinetic mixing between $X$ and the photon. The power counting for the energy growth of the scattering amplitudes is facilitated by isolating the longitudinal enhancement. We examine in detail the interaction with an anomalous global vector current $X_\mu j_{anom}^\mu$, carefully isolating the finite contribution to the fermion triangle diagram. We calculate the longitudinally-enhanced observables $Z \rightarrow X\gamma$ (when $m_X < m_Z$), $f\bar{f} \rightarrow X \gamma$, and $Z\gamma \to Z\gamma$ when $X$ couples to the baryon number current. Introducing a fake gauge-invariance by writing $X^\mu = A^\mu - \partial^\mu \pi/m_X$, the would-be gauge anomaly associated with $A_\mu j_{anom}^\mu$ is canceled by $j_{anom}^\mu \partial_\mu \pi/m_X$; this is the four-dimensional Green-Schwarz anomaly-cancellation mechanism at work. Our analysis suggests there is no free lunch by appealing to Stückelberg for the mass of a vector field: the price paid for avoiding a dark Higgs sector is replaced by the non-generic set of interactions that the Stückelberg vector field must have to avoid amplitudes that grow with energy.

The UT plots played already for three decades an important role in the tests of the SM and the determination of the CKM parameters. As of 2022, among the four CKM parameters, $V_{us}$ and $\beta$ are already measured with respectable precision, while this is not the case of $|V_{cb}|$ and $\gamma$. In the case of $|V_{cb}|$ the main obstacle are the significant tensions between its inclusive and exclusive determinations from tree-level decays. The present uncertainty in $\gamma$ of $4^\circ$ from tree-level decays will be reduced to $1^\circ$ by the LHCb and Belle II collaborations in the coming years. Unfortunately in the UT plots $|V_{cb}|$ is not seen and the experimental improvements in the determination of $\gamma$ from tree-level decays at the level of a few degrees are difficult to appreciate. In view of these deficiencies of the UT plots with respect to $|V_{cb}|$ and $\gamma$ and the central role these two CKM parameters will play in this decade, the recently proposed plots of $|V_{cb}|$ versus $\gamma$ extracted from various processes appear to be superior to the UT plots in the flavour phenomenology. We illustrate this idea with $\Delta M_s$, $\Delta M_d$, $\epsilon_K$ and with rare decays $B_s\to\mu^+\mu^-$, $B_d\to\mu^+\mu^-$, $K^+\to \pi^+\nu\bar\nu$ and $K_L\to\pi^0\nu\bar\nu$. The power of $\epsilon_K$, $K^+\to\pi^+\nu\bar\nu)$ and $K_{L}\to\pi^0\nu\bar\nu)$ in the determination of $|V_{cb}|$, due to their strong dependence on $|V_{cb}|$, is transparently exhibited in this manner. Combined with future reduced errors on $\gamma$ and $|V_{cb}|$ from tree-level decays such plots can better exhibit possible inconsistenices between various determinations of these two parameters, caused by new physics, than it is possible with the UT plots. This can already be illustrated on the example of the $2.7\sigma$ anomaly in $B_s\to\mu^+\mu^-$.

We complete the calculation of the three-gluon-emission contribution to the same-hemisphere part of the zero-jettiness soft function at next-to-next-to-next-to-leading order in perturbative QCD.

Using the Schwinger-Keldysh-formalism, reformulated in arXiv:2108.01695 as an effective field theory in Euclidean anti-de Sitter, we evaluate the one-loop cosmological four-point function of a conformally coupled interacting scalar field in de Sitter. Recasting the Witten cosmological correlator as flat space Feynman integrals, we evaluate the one-loop cosmological four-point functions in de Sitter space in terms of single-valued multiple polylogarithms. From it we derive anomalous dimensions and OPE coefficients of the dual conformal field theory at space-like, future infinity. In particular, we find an interesting degeneracy in the anomalous dimensions relating operators of neighboring spins.

We demonstrate how to use persistent homology for cosmological parameter inference in a tomographic cosmic shear survey. We obtain the first cosmological parameter constraints from persistent homology by applying our method to the first-year data of the Dark Energy Survey. To obtain these constraints, we analyse the topological structure of the matter distribution by extracting persistence diagrams from signal-to-noise maps of aperture masses. This presents a natural extension to the widely used peak count statistics. Extracting the persistence diagrams from the cosmo-SLICS, a suite of $N$-body simulations with variable cosmological parameters, we interpolate the signal using Gaussian Processes and marginalise over the most relevant systematic effects, including intrinsic alignments and baryonic effects. We find for the structure growth parameter $S_8=0.747^{+0.025}_{-0.031}$, which is in full agreement with other late-time probes. We also constrain the intrinsic alignment parameter to $A=1.54\pm 0.52$, ruling out the case of no intrinsic alignments at a $3\sigma$-level.

Starting from first principles, we study radiative transfer by new feebly-interacting bosons (FIBs) such as axions, axion-like particles (ALPs), dark photons, and others. Our key simplification is to include only boson emission or absorption (including decay), but not scattering between different modes of the radiation field. Based on a given distribution of temperature and FIB absorption rate in a star, we derive explicit volume-integral expressions for the boson luminosity, reaching from the free-streaming to the strong-trapping limit. The latter is seen explicitly to correspond to quasi-thermal emission from a "FIB sphere" according to the Stefan-Boltzmann law. Our results supersede expressions and approximations found in the recent literature on FIB emission from a supernova core and, for radiatively unstable FIBs, provide explicit expressions for the nonlocal ("ballistic") transfer of energy recently discussed in horizontal-branch stars.

If gauge fields are coupled to an axion field during inflation, they can lead to unique observational signatures. However, this system often shows strong backreaction effects, invalidating the standard perturbation theory approach. In this work, we present the first nonlinear lattice simulation of an axion-U(1) system during inflation. We use it to fully characterize the statistics of the comoving curvature perturbation $\zeta$. We find that non-Gaussianity of $\zeta$ is large in the linear regime, whereas it is suppressed when the dynamics becomes nonlinear. This relaxes bounds from overproduction of primordial black holes, allowing for an observable gravitational waves signal at interferometer scales.

In this paper, we assess the impact of numerical resolution and of the implementation of energy input from AGN feedback models on the inner structure of cluster sub-haloes in hydrodynamic simulations. We compare several zoom-in re-simulations of a sub-sample of the cluster-sized haloes studied in Meneghetti et al. (2020), obtained by varying mass resolution, softening length and AGN energy feedback scheme. We study the impact of these different setups on the subhalo abundances, their radial distribution, their density and mass profiles and the relation between the maximum circular velocity, which is a proxy for subhalo compactness. Regardless of the adopted numerical resolution and feedback model, subhaloes with masses Msub < 1e11Msun/h, the most relevant mass-range for galaxy-galaxy strong lensing, have maximum circular velocities ~30% smaller than those measured from strong lensing observations of Bergamini et al. (2019). We also find that simulations with less effective AGN energy feedback produce massive subhaloes (Msub> 1e11 Msun/h ) with higher maximum circular velocity and that their Vmax - Msub relation approaches the observed one. However the stellar-mass number count of these objects exceeds the one found in observations and we find that the compactness of these simulated subhaloes is the result of an extremely over-efficient star formation in their cores, also leading to larger-than-observed subhalo stellar mass. We conclude that simulations are unable to simultaneously reproduce the observed stellar masses and compactness (or maximum circular velocities) of cluster galaxies. Thus, the discrepancy between theory and observations that emerged from the analysis of Meneghetti et al. (2020) persists. It remains an open question as to whether such a discrepancy reflects limitations of the current implementation of galaxy formation models or the LCDM paradigm.

We report the discovery of a multi-planetary system transiting the M0 V dwarf HD 260655 (GJ 239, TOI-4599). The system consists of at least two transiting planets, namely HD 260655 b, with a period of 2.77 d, a radius of R$_b$ = 1.240$\pm$0.023 R$_\oplus$, a mass of M$_b$ = 2.14$\pm$0.34 M$_\oplus$, and a bulk density of $\rho_b$ = 6.2$\pm$1.0 g cm$^{-3}$, and HD 260655 c, with a period of 5.71 d, a radius of R$_c$ = 1.533$^{+0.051}_{-0.046}$ R$_\oplus$, a mass of M$_c$ = 3.09$\pm$0.48 M$_\oplus$, and a bulk density of $\rho_c$ = 4.7$^{+0.9}_{-0.8}$ g cm$^{-3}$. The planets were detected in transit by the TESS mission and confirmed independently with archival and new precise radial velocities obtained with the HIRES and CARMENES instruments since 1998 and 2016, respectively. At a distance of 10 pc, HD 260655 becomes the fourth closest known multi-transiting planet system after HD 219134, LTT 1445 A, and AU Mic. Due to the apparent brightness of the host star (J = 6.7 mag), both planets are among the most suitable rocky worlds known today for atmospheric studies with the JWST, both in transmission and emission.

The dark matter halo sparsity, i.e. the ratio between spherical halo masses enclosing two different overdensities, provides a non-parametric proxy of the halo mass distribution which has been shown to be a sensitive probe of the cosmological imprint encoded in the mass profile of haloes hosting galaxy clusters. Mass estimations at several overdensities would allow for multiple sparsity measurements, that can potentially retrieve the entirety of the cosmological information imprinted on the halo profile. Here, we investigate the impact of multiple sparsity measurements on the cosmological model parameter inference. For this purpose, we analyse N-body halo catalogues from the Raygal and M2Csims simulations and evaluate the correlations among six different sparsities from Spherical Overdensity halo masses at $\Delta=200,500,1000$ and $2500$ (in units of the critical density). Remarkably, sparsities associated to distinct halo mass shells are not highly correlated. This is not the case for sparsities obtained using halo masses estimated from the Navarro-Frenk-White (NFW) best-fit profile, that artificially correlates different sparsities to order one. This implies that there is additional information in the mass profile beyond the NFW parametrization and that it can be exploited with multiple sparsities. In particular, from a likelihood analysis of synthetic average sparsity data, we show that cosmological parameter constraints significantly improve when increasing the number of sparsity combinations, though the constraints saturate beyond four sparsity estimates. We forecast constraints for the CHEX-MATE cluster sample and find that systematic mass bias errors mildly impact the parameter inference, though more studies are needed in this direction.

We introduce an open-source package called QTraj that solves the Lindblad equation for heavy-quarkonium dynamics using the quantum trajectories algorithm. The package allows users to simulate the suppression of heavy-quarkonium states using externally-supplied input from 3+1D hydrodynamics simulations. The code uses a split-step pseudo-spectral method for updating the wave-function between jumps, which is implemented using the open-source multi-threaded FFTW3 package. This allows one to have manifestly unitary evolution when using real-valued potentials. In this paper, we provide detailed documentation of QTraj 1.0, installation instructions, and present various tests and benchmarks of the code.

We analyze the flavor violating muon decay μ → eχ, where χ is a massive gauge boson, with emphasis in the regime where χ is ultralight. We first study this process from an effective field theory standpoint in terms of form factors. We then present two explicit models where μ → eχ is generated at tree level and at the one-loop level. We also comment on the prospects of observing the process μ → eχ in view of the current limits on μ → 3 e from the SINDRUM collaboration.

We study the evolution of dust in a cosmological volume using a hydrodynamical simulation in which the dust production is coupled with the MUPPI (MUlti Phase Particle Integrator) sub-resolution model of star formation and feedback. As for the latter, we keep as reference the model setup calibrated previously to match the general properties of Milky Way like galaxies in zoom-in simulations. However, we suggest that an increase of the star formation efficiency with the local dust to gas ratio would better reproduce the observed evolution of the cosmic star formation density. Moreover, the paucity of quenched galaxies at low redshift demands a stronger role of AGN feedback. We tune the parameters ruling direct dust production from evolved stars and accretion in the inter stellar medium to get scaling relations involving dust, stellar mass and metallicity in good agreement with observations. In low mass galaxies the accretion process is inefficient. As a consequence, they remain poorer in silicate and small grains than higher mass ones. We reproduce reasonably well the few available data on the radial distribution of dust outside the galactic region, supporting the assumption that the dust and gas dynamics are well coupled at galactic scales.

Knowing the Galactic 3D dust distribution is relevant for understanding many processes in the interstellar medium and for correcting many astronomical observations for dust absorption and emission. Here, we aim for a 3D reconstruction of the Galactic dust distribution with an increase in the number of meaningful resolution elements by orders of magnitude with respect to previous reconstructions, while taking advantage of the dust's spatial correlations to inform the dust map. We use iterative grid refinement to define a log-normal process in spherical coordinates. This log-normal process assumes a fixed correlation structure, which was inferred in an earlier reconstruction of Galactic dust. Our map is informed through 111 Million data points, combining data of PANSTARRS, 2MASS, Gaia DR2 and ALLWISE. The log-normal process is discretized to 122 Billion degrees of freedom, a factor of 400 more than our previous map. We derive the most probable posterior map and an uncertainty estimate using natural gradient descent and the Fisher-Laplace approximation. The dust reconstruction covers a quarter of the volume of our Galaxy, with a maximum coordinate distance of $16\,\text{kpc}$, and meaningful information can be found up to at distances of $4\,$kpc, still improving upon our earlier map by a factor of 5 in maximal distance, of $900$ in volume, and of about eighteen in angular grid resolution. Unfortunately, the maximum posterior approach chosen to make the reconstruction computational affordable introduces artifacts and reduces the accuracy of our uncertainty estimate. Despite of the apparent limitations of the presented 3D dust map, a good part of the reconstructed structures are confirmed by independent maser observations. Thus, the map is a step towards reliable 3D Galactic cartography and already can serve for a number of tasks, if used with care.

Meneghetti et al. (2020) recently reported an excess of galaxy-galaxy strong lensing (GGSL) in galaxy clusters compared to expectations from the LCDM cosmological model. Theoretical estimates of the GGSL probability are based on the analysis of numerical hydrodynamical simulations in the LCDM cosmology. We quantify the impact of the numerical resolution and AGN feedback scheme adopted in cosmological simulations on the predicted GGSL probability and determine if varying these simulation properties can alleviate the gap with observations. We repeat the analysis of Meneghetti et al. (2020) on cluster-size halos simulated with different mass and force resolutions and implementing several independent AGN feedback schemes. We find that improving the mass resolution by a factor of ten and twenty-five, while using the same galaxy formation model that includes AGN feedback, does not affect the GGSL probability. We find similar results regarding the choice of gravitational softening. On the contrary, adopting an AGN feedback scheme that is less efficient at suppressing gas cooling and star formation leads to an increase in the GGSL probability by a factor between three and six. However, we notice that such simulations form overly massive subhalos whose contribution to the lensing cross-section would be significant while their Einstein radii are too large to be consistent with the observations. The primary contributors to the observed GGSL cross-sections are subhalos with smaller masses, that are compact enough to become critical for lensing. The population with these required characteristics appears to be absent in simulations.

We perform two distinct spatio-spectral reconstructions of the gamma-ray sky in the range of 0.56-316 GeV based on Fermi Large Area Telescope (LAT) data. Both describe the sky brightness to be composed of a diffuse-emission and a point-source component. The first model requires minimal assumptions and provides a template-free reconstruction as a reference. It makes use of spatial and spectral correlations to distinguish between the different components. The second model is physics-informed and further differentiates between diffuse emission of hadronic and leptonic origin. For this, we assume parametric, but spatially varying energy spectra to distinguish between the processes and use thermal Galactic dust observations to indicate the preferred sites of hadronic interactions. To account for instrumental effects we model the point-spread, the energy dispersion, and the exposure of the telescope throughout the observation. The reconstruction problem is formulated as a Bayesian inference task, that is solved by variational inference. We show decompositions of the Gamma-ray flux into diffuse and point-like emissions, and of the diffuse emissions into multiple physically motivated components. The diffuse decomposition provides an unprecedented view of the Galactic leptonic diffuse emission. It shows the Fermi bubbles and their spectral variations in high fidelity and other areas exhibiting strong cosmic ray electron contents, such as a thick disk in the inner Galaxy and outflow regions. Furthermore, we report a hard spectrum gamma ray arc in the northern outer bubble co-spatial with the reported X-ray arc by the eROSITA collaboration. All our spatio-spectral sky reconstructions and their uncertainty quantification are publicly available.

In this note, as an input to the Snowmass studies, we provide a broad-brush picture of the physics output of future colliders as a function of their center of mass energies and luminosities. Instead of relying on precise projections of physics reaches, which are lacking in many cases, we mainly focused on simple benchmarks of physics yields, such as the number of Higgs boson produced. More detailed considerations for lepton colliders are given since there have been various recent proposals. A brief summary for hadron colliders based on a simple scaling estimate of the physics reaches is also included.

We show that, in addition to the counting of canonical dimensions, a counting of loop orders is necessary to fully specify the power counting of Standard Model Effective Field Theory (SMEFT). Using concrete examples, we demonstrate that considering the canonical dimensions of operators alone may lead to inconsistent results. The counting of both, canonical dimensions and loop orders, establishes a clear hierarchy of the terms in SMEFT. In practice, this serves to identify, and focus on, the potentially dominating effects in any given high-energy process in a meaningful way. Additionally, this will lead to a consistent limitation of free parameters in SMEFT applications.

We provide an extensive study of the lifetimes of singly charmed baryons and mesons, within the heavy quark expansion with all known corrections included. A special attention is devoted to the choice of the charm mass and wavefunctions of heavy baryons. We give our predictions for lifetimes, lifetime ratios, and semileptonic branching ratios of singly charmed baryons. Our results accommodate the experimentally-favoured hierarchy of singly charmed baryon lifetimes \begin{eqnarray*} \tau\left(\Xi_c^{0}\right) < \tau\left(\Lambda_c^{+}\right)< \tau\left(\Omega_c^{0}\right) < \tau\left(\Xi_c^{+}\right)\, \end{eqnarray*} in contrast to earlier theoretical findings. Predictions for charmed meson lifetimes and semileptonic decay rates are in agreement with a recent comprehensive study and experimental results within uncertainties.

Context. The Carina Nebula complex (CNC) is one of the most massive and active star-forming regions in our Galaxy and it contains several large young star clusters. The distances of the individual clusters and their physical connection were poorly known up to now, with strongly discrepant results reported in the literature.
Aims: We want to determine reliable distances of the young stellar clusters in the central Carina Nebula region (in particular, Tr 14, 15, and 16) and the prominent clusters NGC 3324 and NGC 3293 in the northwestern periphery of the CNC.
Methods: We analyzed the parallaxes in Gaia EDR3 for a comprehensive sample of 237 spectroscopically identified OB stars, as well as for 9562 X-ray-selected young stars throughout the complex. We also performed an astrometric analysis to identify members of the young cluster vdBH 99, which is located in the foreground of the northwestern part of the Carina Nebula.
Results: We find that the distances of the investigated clusters in the CNC are equal within ≤2%, and yield very consistent most likely mean distance values of 2.36_−0.05^+0.05 kpc for the OB star sample and 2.34_−0.06^+0.05 kpc for the sample of X-ray-selected young stars.
Conclusions: Our results show that the clusters in the CNC constitute a coherent star-forming region, in particular with regard to NGC 3324 and NGC 3293 at the northwestern periphery, which are (within ≤2%) at the same distance as the central Carina Nebula. For the foreground cluster vdBH 99, we find a mean distance of 441₋₂⁺² pc and an age of ≃60 Myr. We quantified the contamination of X-ray-selected samples of Carina Nebula stars based on members of this foreground cluster.

Table 1 is only available at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/660/A11

Cosmic-ray antideuterons could be a key for the discovery of exotic phenomena in our Galaxy, such as dark-matter annihilations or primordial black hole evaporation. Unfortunately the theoretical predictions of the antideuteron flux at Earth are plagued with uncertainties from the mechanism of antideuteron production and propagation in the Galaxy. We present the most up-to-date calculation of the antideuteron fluxes from cosmic-ray collisions with the interstellar medium and from exotic processes. We include for the first time the antideuteron inelastic interaction cross section recently measured by the ALICE collaboration to account for the loss of antideuterons during propagation. In order to bracket the uncertainty in the expected fluxes, we consider several state-of-the-art models of antideuteron production and of cosmic-ray propagation.