We review the landscape of QCD axion models. Theoretical constructions that extend the window for the axion mass and couplings beyond conventional regions are highlighted and classified. Bounds from cosmology, astrophysics and experimental searches are reexamined and updated.

The RNA world scenario posits replication by RNA polymerases. On early Earth, a geophysical setting is required to separate hybridized strands after their replication and to localize them against diffusion. We present a pointed heat source that drives exponential, RNA-catalyzed amplification of short RNA with high efficiency in a confined chamber. While shorter strands were periodically melted by laminar convection, the temperature gradient caused aggregated polymerase molecules to accumulate, protecting them from degradation in hot regions of the chamber. These findings demonstrate a size-selective pathway for autonomous RNA-based replication in natural nonequilibrium conditions.

This is the first advanced, systematic and comprehensive look at weak decays in the framework of gauge theories. Included is a large spectrum of topics, both theoretical and experimental. In addition to explicit advanced calculations of Feynman diagrams and the study of renormalization group strong interaction effects in weak decays, the book is devoted to the Standard Model Effective Theory, dominating present phenomenology in this field, and to new physics models with the goal of searching for new particles and interactions through quantum fluctuations. This book will benefit theorists, experimental researchers, and Ph.D. students working on flavour physics and weak decays as well as physicists interested in physics beyond the Standard Model. In its concern for the search for new phenomena at short distance scales through the interplay between theory and experiment, this book constitutes a travel guide to physics far beyond the scales explored by the Large Hadron Collider at CERN.

Outflows driven by large-scale magnetic fields likely play an important role in the evolution and dispersal of protoplanetary disks and in setting the conditions for planet formation. We extend our 2D-axisymmetric nonideal MHD model of these outflows by incorporating radiative transfer and simplified thermochemistry, with the dual aims of exploring how heating influences wind launching and illustrating how such models can be tested through observations of diagnostic spectral lines. Our model disks launch magnetocentrifugal outflows primarily through magnetic tension forces, so the mass-loss rate increases only moderately when thermochemical effects are switched on. For typical field strengths, thermochemical and irradiation heating are more important than magnetic dissipation. We furthermore find that the entrained vertical magnetic flux diffuses out of the disk on secular timescales as a result of nonideal MHD. Through postprocessing line radiative transfer, we demonstrate that spectral line intensities and moment-1 maps of atomic oxygen, the HCN molecule, and other species show potentially observable differences between a model with a magnetically driven outflow and one with a weaker, photoevaporative outflow. In particular, the line shapes and velocity asymmetries in the moment-1 maps could enable the identification of outflows emanating from the disk surface.

We present a blind time-delay cosmographic analysis for the lens system DES J0408-5354. This system is extraordinary for the presence of two sets of multiple images at different redshifts, which provide the opportunity to obtain more information at the cost of increased modelling complexity with respect to previously analysed systems. We perform detailed modelling of the mass distribution for this lens system using three band Hubble Space Telescope imaging. We combine the measured time delays, line-of-sight central velocity dispersion of the deflector, and statistically constrained external convergence with our lens models to estimate two cosmological distances. We measure the 'effective' time-delay distance corresponding to the redshifts of the deflector and the lensed quasar $D_{\Delta t}^{\rm eff}=$ $3382_{-115}^{+146}$ Mpc and the angular diameter distance to the deflector D_d = $1711_{-280}^{+376}$ Mpc, with covariance between the two distances. From these constraints on the cosmological distances, we infer the Hubble constant H₀= $74.2_{-3.0}^{+2.7}$ km s^-1 Mpc^-1 assuming a flat ΛCDM cosmology and a uniform prior for Ω_m as $\Omega _{\rm m} \sim \mathcal {U}(0.05, 0.5)$ . This measurement gives the most precise constraint on H₀ to date from a single lens. Our measurement is consistent with that obtained from the previous sample of six lenses analysed by the H₀ Lenses in COSMOGRAIL's Wellspring (H0LiCOW) collaboration. It is also consistent with measurements of H₀ based on the local distance ladder, reinforcing the tension with the inference from early Universe probes, for example, with 2.2σ discrepancy from the cosmic microwave background measurement.

Recent stacked ALMA observations have revealed that normal, star-forming galaxies at z ≈ 6 are surrounded by extended (≈10 kpc) [C II]-emitting haloes, which are not predicted by the most advanced, zoom-in simulations. We present a model in which these haloes are the result of supernova-driven cooling outflows. Our model contains two free parameters, the outflow mass loading factor, η, and the parent galaxy dark matter halo circular velocity, V_c. The outflow model successfully matches the observed [C II] surface brightness profile if η = 3.20 ± 0.10 and $v_{\rm c} = 170 \pm 10 \, \rm km\, s^{-1}$ , corresponding to a dynamical mass of ${\approx }10^{11}\, {\rm M}_{\odot }$ . The predicted outflow rate and velocity range are $128 \pm 5\, {\rm M}_{\odot }\, {\rm yr}^{-1}$ and 300-500 $\, \rm km\, s^{-1}$ , respectively. We conclude that (a) extended haloes can be produced by cooling outflows; (b) the large η value is marginally consistent with starburst-driven outflows, but it might indicate additional energy input from active galactic nuclei; and (c) the presence of [C II] haloes requires an ionizing photon escape fraction from galaxies f_esc ≪ 1. The model can be readily applied also to individual high-z galaxies, as those observed, e.g. by the ALMA ALPINE survey now becoming available.

We study perturbation theory for large-scale structure in the most general scalar-tensor theories propagating a single scalar degree of freedom, which include Horndeski theories and beyond. We model the parameter space using the effective field theory of dark energy. For Horndeski theories, the gravitational field and fluid equations are invariant under a combination of time-dependent transformations of the coordinates and fields. This symmetry allows one to construct a physical adiabatic mode which fixes the perturbation-theory kernels in the squeezed limit and ensures that the well-known consistency relations for large-scale structure, originally derived in general relativity, hold in modified gravity as well. For theories beyond Horndeski, instead, one generally cannot construct such an adiabatic mode. Because of this, the perturbation-theory kernels are modified in the squeezed limit and the consistency relations for large-scale structure do not hold. We show, however, that the modification of the squeezed limit depends only on the linear theory. We investigate the observational consequences of this violation by computing the matter bispectrum. In the squeezed limit, the largest effect is expected when considering the cross-correlation between different tracers. Moreover, the individual contributions to the 1-loop matter power spectrum do not cancel in the infrared limit of the momentum integral, modifying the power spectrum on nonlinear scales.

The accuracy of the Hubble constant measured with extragalactic Cepheids depends on robust photometry and background estimation in the presence of stellar crowding. The conventional approach accounts for crowding by sampling backgrounds near Cepheids and assuming that they match those at their positions. We show a direct consequence of crowding by unresolved sources at Cepheid sites is a reduction in the fractional amplitudes of their light curves. We use a simple analytical expression to infer crowding directly from the light curve amplitudes of >200 Cepheids in three Type Ia supernovae hosts and NGC 4258 as observed by Hubble Space Telescope—the first near-infrared amplitudes measured beyond the Magellanic Clouds. Where local crowding is minimal, we find near-infrared amplitudes match Milky Way Cepheids at the same periods. At greater stellar densities we find that the empirically measured amplitudes match the values predicted (with no free parameters) from crowding assessed in the conventional way from local regions, confirming their accuracy for estimating the background at the Cepheid locations. Extragalactic Cepheid amplitudes would need to be ∼20% smaller than measured to indicate additional, unrecognized crowding as a primary source of the present discrepancy in H₀. Rather, we find the amplitude data constrains a systematic mis-estimate of Cepheid backgrounds to be 0.029 ± 0.037 mag, more than 5× smaller than the size of the present ∼0.2 mag tension in H₀. We conclude that systematic errors in Cepheid backgrounds do not provide a plausible resolution to the Hubble tension.

The QCD axion provides an elegant solution to the strong C P problem. While the minimal realization is vulnerable to the so-called "axion quality problem," we will consider a more robust realization in the presence of a mirror sector related to the standard model by a (softly broken) Z₂ symmetry. We point out that the resulting "heavy" axion, while satisfying all theoretical and observational constraints, has a large and uncharted parameter space, which allows it to be probed at the LHC as a long-lived particle (LLP). The small defining axionic coupling to gluons results in a challenging hadronic decay signal which we argue can be distinguished against the background in such a long-lived regime, and yet, the same coupling allows for sufficient production at the hadron colliders thanks to the large gluon-parton luminosity. Our study opens up a new window towards accelerator observable axions and, more generally, singly produced LLPs.

We study the bottomonium spectrum using a relativistic potential model in the momentum space. This model is based on a complete one gluon exchange interaction with a momentum dependent screening factor to account for the effects due to virtual pair creation that appear close to the decay thresholds. The overall model does not make use of nonrelativistic approximations. We fit well established bottomonium states below the open bottom threshold and predict the rest of the spectrum up to ≈11200 MeV and J^PC=3^-- . Uncertainties are treated rigorously and propagated in full to the parameters of the model using a Monte Carlo to identify if which deviations from experimental data can be absorbed into the statistical uncertainties of the models and which can be related to physics beyond the b b ¯ picture, guiding future research. We get a good description of the spectrum, in particular the Belle measurement of the η_b(2 S ) state and the Υ (10860 ) and χ_b(3 P ) resonances.

In this paper we examine the viability of inflation models with a spectator axion field coupled to both gravitational and SU(2) gauge fields via Chern-Simons couplings. Requiring phenomenological success of the axion-SU(2) sector constrains the coupling strength of the gravitational Chern-Simons term. We find that the impact of this term on the production and propagation of gravitational waves can be as large as fifty percent enhancement for the helicity that is not sourced by the gauge field, if the cut-off scale is as low as Λ = 20H. The effect becomes smaller for a larger value of Λ, while the impact on the helicity sourced by the gauge field is negligible regardless of Λ.

We revisit techniques for performing cosmological simulations with both baryons and cold dark matter when each fluid has different initial conditions, as is the case at the end of the radiation era. Most simulations do not reproduce the linear prediction for the difference between the cold dark matter and baryon perturbations. We show that this is due to the common use of offset regular grids when setting up the particle initial conditions. The desired linear evolution can be obtained without any loss of simulation resolution by using a Lagrangian glass for the baryon particles. We further show that the difference between cold dark matter and baryons may affect predictions for the Lyman-α forest flux power spectrum at the 5% level, potentially impacting current cosmological constraints.

We use functional methods to compute one-loop effects in Heavy Quark Effective Theory. The covariant derivative expansion technique facilitates the efficient extraction of matching coefficients and renormalization group evolution equations. This paper pro- vides the first demonstration that such calculations can be performed through the algebraic evaluation of the path integral for the class of effective field theories that are (i) constructed using a non-trivial one-to-many mode decomposition of the UV theory, and (ii) valid for non-relativistic kinematics. We discuss the interplay between operators that appear at intermediate steps and the constraints imposed by the residual Lorentz symmetry that is encoded as reparameterization invariance within the effective description. The tools presented here provide a systematic approach for computing corrections to higher order in the heavy mass expansion; precision applications include predictions for experimental data and connections to theoretical tests via lattice QCD. A set of pedagogical appendices comprehensively reviews modern approaches to performing functional calculations algebraically, and derives contributions from a term with open covariant derivatives for the first time.

With the spatial resolution of the Atacama Large Millimetre Array (ALMA), dusty galaxies in the distant Universe typically appear as single, compact blobs of dust emission, with a median half-light radius, ≍1 kpc. Occasionally, strong gravitational lensing by foreground galaxies or galaxy clusters has probed spatial scales 1-2 orders of magnitude smaller, often revealing late-stage mergers, sometimes with tantalizing hints of sub-structure. One lensed galaxy in particular, the Cosmic Eyelash at z = 2.3, has been cited extensively as an example of where the interstellar medium exhibits obvious, pronounced clumps, on a spatial scale of ≍100 pc. Seven orders of magnitude more luminous than giant molecular clouds in the local Universe, these features are presented as circumstantial evidence that the blue clumps observed in many z ∼ 2-3 galaxies are important sites of ongoing star formation, with significant masses of gas and stars. Here, we present data from ALMA which reveal that the dust continuum of the Cosmic Eyelash is in fact smooth and can be reproduced using two Sérsic profiles with effective radii, 1.2 and 4.4 kpc, with no evidence of significant star-forming clumps down to a spatial scale of ≍80 pc and a star formation rate of <3 M_⊙ yr^-1.

The mass function for black holes and neutron stars at birth is explored for mass-losing helium stars. These should resemble, more closely than similar studies of single hydrogen-rich stars, the results of evolution in close binary systems. The effects of varying the mass-loss rate and metallicity are calculated using a simple semi-analytic approach to stellar evolution that is tuned to reproduce detailed numerical calculations. Though the total fraction of black holes made in stellar collapse events varies considerably with metallicity, mass-loss rate, and mass cutoff, from 5% to 30%, the shapes of their birth functions are very similar for all reasonable variations in these quantities. Median neutron star masses are in the range 1.32-1.37 ${M}_{\odot }$ regardless of metallicity. The median black hole mass for solar metallicity is typically 8-9 ${M}_{\odot }$ if only initial helium cores below 40 ${M}_{\odot }$ (ZAMS mass less than 80 ${M}_{\odot }$ ) are counted, and 9-13 ${M}_{\odot }$, in most cases, if helium cores with initial masses up to 150 ${M}_{\odot }$ (ZAMS mass less than 300 ${M}_{\odot }$ ) contribute. As long as the mass-loss rate as a function of mass exhibits no strong nonlinearities, the black hole birth function from 15 to 35 ${M}_{\odot }$ has a slope that depends mostly on the initial mass function for main-sequence stars. These findings imply the possibility of constraining the initial mass function and the properties of mass loss in close binaries using ongoing measurements of gravitational-wave radiation. The expected rotation rates of the black holes are briefly discussed.

Early-type galaxies - slow and fast rotating ellipticals (E-SRs and E-FRs) and S0s/lenticulars - define a Fundamental Plane (FP) in the space of half-light radius R_e, enclosed surface brightness I_e, and velocity dispersion σ_e. Since I_e and σ_e are distance-independent measurements, the thickness of the FP is often expressed in terms of the accuracy with which I_e and σ_e can be used to estimate sizes R_e. We show that: (1) The thickness of the FP depends strongly on morphology. If the sample only includes E-SRs, then the observed scatter in R_e is ∼ 16 per cent, of which only ∼ 9 per cent is intrinsic. Removing galaxies with M_* < 10¹¹ M_⊙ further reduces the observed scatter to ∼ 13 per cent (∼ 4 per cent intrinsic). The observed scatter increases to ∼ 25 per cent usually quoted in the literature if E-FRs and S0s are added. If the FP is defined using the eigenvectors of the covariance matrix of the observables, then the E-SRs again define an exceptionally thin FP, with intrinsic scatter of only 5 per cent orthogonal to the plane. (2) The structure within the FP is most easily understood as arising from the fact that I_e and σ_e are nearly independent, whereas the R_e-I_e and R_e-σ_e correlations are nearly equal and opposite. (3) If the coefficients of the FP differ from those associated with the virial theorem the plane is said to be 'tilted'. If we multiply I_e by the global stellar mass-to-light ratio M_*/L and we account for non-homology across the population by using Sérsic photometry, then the resulting stellar mass FP is less tilted. Accounting self-consistently for M_*/L gradients will change the tilt. The tilt we currently see suggests that the efficiency of turning baryons into stars increases and/or the dark matter fraction decreases as stellar surface brightness increases.

Supernovae (SNe) generate hot gas in the interstellar medium (ISM), help setting the ISM structure, and support the driving of outflows. It is important to resolve the hot gas generation for galaxy formation simulations at solar mass and sub-parsec resolution that realize individual SN explosions with ambient densities varying by several orders of magnitude in a realistic multiphase ISM. We test resolution requirements by simulating SN blast waves at three metallicities (Z = 0.01, 0.1, and 1 Z_⊙), six densities and their respective equilibrium chemical compositions (n = 0.001-100 cm^-3), and four mass resolutions (0.1-100 M_⊙), in three dimensions. We include non-equilibrium cooling and chemistry, a homogeneous interstellar radiation field, and shielding with a modern pressure-energy smoothed particle hydrodynamics method including isotropic thermal conduction and a meshless-finite-mass solver. We find stronger resolution requirements for chemistry and hot phase generation than for momentum generation. While at 10 M_⊙ the radial momenta at the end of the Sedov phase start converging, the hot phase generation and chemistry require higher resolutions to represent the neutral-to-ionized hydrogen fraction at the end of the Sedov phase correctly. Thermal conduction typically reduces the hot phase by 0.2 dex and has little impact on the chemical composition. In general, our 1 and 0.1 M_⊙ results agree well with previous numerical and analytic estimates. We conclude that for the thermal energy injection SN model presented here resolutions higher than 10 M_⊙ are required to model the chemistry, momentum, and hot phase generation in the multiphase ISM.

In order to detect high frequency gravitational waves, we need a new detection method. In this paper, we develop a formalism for a gravitational wave detector using magnons in a cavity. Using Fermi normal coordinates and taking the non-relativistic limit, we obtain a Hamiltonian for magnons in gravitational wave backgrounds. Given the Hamiltonian, we show how to use the magnons for detecting high frequency gravitational waves. Furthermore, as a demonstration of the magnon gravitational wave detector, we give upper limits on GHz gravitational waves by utilizing known results of magnon experiments for an axion dark matter search.

We revisit our previous work [Capozzi et al., Phys. Rev. D 95, 096014 (2017), 10.1103/PhysRevD.95.096014] where neutrino oscillation and nonoscillation data were analyzed in the standard framework with three neutrino families, in order to constrain their absolute masses and to probe their ordering (either normal, NO, or inverted, IO). We include updated oscillation results to discuss best fits and allowed ranges for the two squared mass differences δ m² and Δ m², the three mixing angles θ₁₂, θ₂₃, and θ₁₃, as well as constraints on the C P -violating phase δ , plus significant indications in favor of NO vs IO at the level of Δ χ²=10.0 . We then consider nonoscillation data from beta decay, from neutrinoless double beta decay (if neutrinos are Majorana), and from various cosmological input variants (in the data or the model) leading to results dubbed as default, aggressive, and conservative. In the default option, we obtain from nonoscillation data an extra contribution Δ χ²≃2.2 in favor of NO, and an upper bound on the sum of neutrino masses Σ <0.15 eV at 2 σ ; both results—dominated by cosmology—can be strengthened or weakened by using more aggressive or conservative options, respectively. Taking into account such variations, we find that the combination of all (oscillation and nonoscillation) neutrino data favors NO at the level of 3.2 -3.7 σ , and that Σ is constrained at the 2 σ level within Σ <0.12 - 0.69 eV . The upper edge of this allowed range corresponds to an effective β -decay neutrino mass m_β≃Σ /3 ≃0.23 eV , at the sensitivity frontier of the KATRIN experiment.

Neutrinos are unique probes of core-collapse supernova dynamics, especially in the case of black hole (BH-)forming stellar collapses, where the electromagnetic emission may be faint or absent. By investigating two three-dimensional hydrodynamical simulations of BH-forming stellar collapses of mass 40 M_⊙ and 75 M_⊙, we identify the physical processes preceding BH formation through neutrinos and forecast the neutrino signal expected in the existing IceCube and Super-Kamiokande detectors, as well as in the future generation DUNE facility. Prior to the abrupt termination of the neutrino signal corresponding to BH formation, both models develop episodes of strong and long-lasting activity by the spiral standing accretion shock instability (SASI). We find that the spiral SASI peak in the Fourier power spectrum of the neutrino event rate will be distinguishable at 3 σ above the detector noise for distances up to ∼O (30 ) kpc in the most optimistic scenario, with IceCube having the highest sensitivity. Interestingly, given the long duration of the spiral SASI episodes, the spectrograms of the expected neutrino event rate carry clear signs of the evolution of the spiral SASI frequency as a function of time, as the shock radius and postshock fluid velocity evolve. Because of the high accretion luminosity and its large-amplitude SASI-induced modulations, any contribution from asymmetric (dipolar or quadrupolar) neutrino emission associated with the lepton emission self-sustained asymmetry is far subdominant in the neutrino signal.

The violation of baryon number, , is an essential ingredient for the preferential creation of matter over antimatter needed to account for the observed baryon asymmetry in the Universe. However, such a process has yet to be experimentally observed. The HIBEAM/NNBAR program is a proposed two-stage experiment at the European Spallation Source to search for baryon number violation. The program will include high-sensitivity searches for processes that violate baryon number by one or two units: free neutron–antineutron oscillation () via mixing, neutron–antineutron oscillation via regeneration from a sterile neutron state (), and neutron disappearance (n → n′); the effective process of neutron regeneration () is also possible. The program can be used to discover and characterize mixing in the neutron, antineutron and sterile neutron sectors. The experiment addresses topical open questions such as the origins of baryogenesis and the nature of dark matter, and is sensitive to scales of new physics substantially in excess of those available at colliders. A goal of the program is to open a discovery window to neutron conversion probabilities (sensitivities) by up to three orders of magnitude compared with previous searches. The opportunity to make such a leap in sensitivity tests should not be squandered. The experiment pulls together a diverse international team of physicists from the particle (collider and low energy) and nuclear physics communities, while also including specialists in neutronics and magnetics.

We review the present status of the Standard Model calculation of the anomalous magnetic moment of the muon. This is performed in a perturbative expansion in the fine-structure constant α and is broken down into pure QED, electroweak, and hadronic contributions. The pure QED contribution is by far the largest and has been evaluated up to and including O(α5) with negligible numerical uncertainty. The electroweak contribution is suppressed by (mμ∕MW)2 and only shows up at the level of the seventh significant digit. It has been evaluated up to two loops and is known to better than one percent. Hadronic contributions are the most difficult to calculate and are responsible for almost all of the theoretical uncertainty. The leading hadronic contribution appears at O(α2) and is due to hadronic vacuum polarization, whereas at O(α3) the hadronic light-by-light scattering contribution appears. Given the low characteristic scale of this observable, these contributions have to be calculated with nonperturbative methods, in particular, dispersion relations and the lattice approach to QCD. The largest part of this review is dedicated to a detailed account of recent efforts to improve the calculation of these two contributions with either a data-driven, dispersive approach, or a first-principle, lattice-QCD approach. The final result reads aμSM=116591810(43)×10−11 and is smaller than the Brookhaven measurement by 3.7 σ . The experimental uncertainty will soon be reduced by up to a factor four by the new experiment currently running at Fermilab, and also by the future J-PARC experiment. This and the prospects to further reduce the theoretical uncertainty in the near future – which are also discussed here – make this quantity one of the most promising places to look for evidence of new physics.

We calculate the step-scaling function, the lattice analog of the renormalization group β -function, for an SU(3) gauge theory with ten fundamental flavors. We present a detailed analysis including the study of systematic effects of our extensive data set generated with ten dynamical flavors using the Symanzik gauge action and three times stout smeared Möbius domain wall fermions. Using up to 32⁴ volumes, we calculate renormalized couplings for different gradient flow schemes and determine the step-scaling β function for a scale change s =2 on up to five different lattice volume pairs. In an accompanying paper we discuss that gradient flow can promote lattice dislocations to instantonlike objects, introducing nonperturbative lattice artifacts to the step-scaling function. Motivated by the observation that Wilson flow sufficiently suppresses these artifacts, we choose Wilson flow with the Symanzik operator as our preferred analysis. We study systematic effects by calculating the step-scaling function based on alternative flows (Zeuthen or Symanzik), alternative operators (Wilson plaquette, clover), and also explore the effects of the perturbative tree-level improvement. Further we investigate the effects due to the finite value of L_s.

We study stellar property statistics, including satellite galaxy occupation, of haloes in three cosmological hydrodynamics simulations: BAHAMAS + MACSIS, IllustrisTNG, and Magneticum Pathfinder. Applying localized linear regression, we extract halo mass-conditioned normalizations, slopes, and intrinsic covariance for (i) N_sat, the number of stellar mass-thresholded satellite galaxies within radius R_200c of the halo; (ii) M_⋆,tot, the total stellar mass within that radius, and (iii) M_⋆,BCG, the gravitationally bound stellar mass of the central galaxy within a 100 kpc radius. The parameters show differences across the simulations, in part from numerical resolution, but there is qualitative agreement for the N_sat - M_⋆,BCG correlation. Marginalizing over M_halo, we find the N_sat kernel, p(ln N_sat | M_halo,z) to be consistently skewed left in all three simulations, with skewness parameter γ = -0.91 ± 0.02, while the M_⋆,tot kernel shape is closer to lognormal. The highest resolution simulations find γ ≃ -0.8 for the z = 0 shape of the M_⋆,BCG kernel. We provide a Gaussian mixture fit to the low-redshift N_sat kernel as well as local linear regression parameters tabulated for M_halo > 10^13.5 M⊙ in all simulations.

The Fundamental Plane (FP) of black hole (BH) activity in galactic nuclei relates X-ray and radio luminosities to BH mass and accretion rate. However, there is a large scatter exhibited by the data, which motivated us for a new variable. We add BH spin as a new variable and estimate the spin dependence of the jet power and disc luminosity in terms of radio and X-ray luminosities. We assume the Blandford-Znajek process as the main source of the outflow, and find that the jet power depends on BH spin stronger than quadratically at moderate and large spin values. We perform a statistical analysis for 10 active galactic nuclei (AGNs) which have sub-Eddington accretion rates and whose spin values are measured independently via the reflection or continuum-fitting methods, and find that the spin-dependent relation describes the data significantly better. This analysis, if supported with more data, could imply not only the spin dependence of the FP relation, but also the Blandford-Znajek process in AGN jets.

In the presence of an external magnetic field, the axion and the photon mix. In particular, the dispersion relation of a longitudinal plasmon always crosses the dispersion relation of the axion (for small axion masses), thus leading to a resonant conversion. Using thermal field theory, we concisely derive the axion emission rate, applying it to astrophysical and laboratory scenarios. For the Sun, depending on the magnetic field profile, plasmon-axion conversion can dominate over Primakoff production at low energies (≲200 eV ). This both provides a new axion source for future helioscopes and, in the event of discovery, would probe the magnetic field structure of the Sun. In the case of white dwarfs (WDs), plasmon-axion conversion provides a pure photon coupling probe of the axion, which may contribute significantly for low-mass WDs. Finally, we rederive and confirm the axion absorption rate of the recently proposed plasma haloscopes.

We carry out ‘full-physics’ hydrodynamical simulations of galaxy formation in the normal-branch Dvali–Gabadadze–Porrati (nDGP) braneworld model using a new modified version of the arepo code and the IllustrisTNG galaxy formation model. We simulate two nDGP models (N5 and N1) that represent, respectively, weak and moderate departures from general relativity (GR), in boxes of sizes |$62$| and |$25\, h^{-1}{\rm Mpc}$| using 2 × 512^3 dark matter particles and initial gas cells. This allows us to explore, for the first time, the impact of baryonic physics on galactic scales in braneworld models of modified gravity and to make predictions on the stellar content of dark matter haloes and galaxy evolution through cosmic time in these models. We find significant differences between the GR and nDGP models in the power spectra and correlation functions of gas, stars and dark matter of up to ∼25 per cent on large scales. Similar to their impact in the standard cosmological model (Λ cold dark matter), baryonic effects can have a significant influence over the clustering of the overall matter distribution, with a sign that depends on scale. Studying the degeneracy between modified gravity and galactic feedback in these models, we find that these two physical effects on matter clustering can be cleanly disentangled, allowing for a method to accurately predict the matter power spectrum with baryonic effects included, without having to run hydrodynamical simulations. Depending on the braneworld model, we find differences compared with GR of up to ∼15 per cent in galaxy properties such as the stellar-to-halo-mass ratio, galaxy stellar mass function, gas fraction, and star formation rate density. The amplitude of the fifth force is reduced by the presence of baryons in the very inner part of haloes, but this reduction quickly becomes negligible above ∼0.1 times the halo radius.

Ultralight bosonic fields are compelling dark-matter candidates and arise in a variety of beyond standard model scenarios. These fields can tap energy and angular momentum from spinning black holes through superradiant instabilities, during which a macroscopic bosonic condensate develops around the black hole. Striking features of this phenomenon include gaps in the spin-mass distribution of astrophysical black holes and a continuous gravitational-wave (GW) signal emitted by the condensate. So far these processes have been studied in great detail for scalar fields and, more recently, for vector fields. Here we take an important step forward in the black hole superradiance program by computing, analytically, the instability timescale, direct GW emission, and stochastic background, in the case of massive tensor (i.e., spin-2) fields. Our analysis is valid for any black hole spin and for small boson masses. The instability of massive spin-2 fields shares some properties with the scalar and vector cases, but its phenomenology is much richer, for example, there exist multiple modes with comparable instability timescales, and the dominant GW signal is hexadecapolar rather than quadrupolar. Electromagnetic and GW observations of spinning black holes in the mass range M ∈(1 ,10¹⁰) M_⊙ can constrain the mass of a putative spin-2 field in the range 10^-22≲m_b c²/eV ≲10^-10 . For 10^-17≲m_b c²/eV ≲10^-15 , the space mission LISA could detect the continuous GW signal for sources at redshift z =20 , or even larger.

Upcoming surveys will use a variety of galaxy selections to map the large-scale structure of the Universe. It is important to make accurate predictions for the properties and clustering of such galaxies, including the errors on these statistics. Here, we describe a novel technique which uses the semi-analytical model of galaxy formation galform, embedded in the high-resolution N-body Planck-Millennium simulation, to populate a thousand halo catalogues generated using the Parallel-PM N-body glam code. Our hybrid scheme allows us to make clustering predictions on scales that cannot be modelled in the original N-body simulation. We focus on luminous red galaxies (LRGs) selected in the redshift range z = 0.6 − 1 from the galform output using similar colour-magnitude cuts in the r, z, and W1 bands to those that will be applied in the Dark Energy Spectroscopic Instrument (DESI) survey, and call this illustrative sample ‘DESI-like’ LRGs. We find that the LRG-halo connection is non-trivial, leading to the prediction of a non-standard halo occupation distribution; in particular, the occupation of central galaxies does not reach unity for the most massive haloes, and drops with increasing mass. The glam catalogues reproduce the abundance and clustering of the LRGs predicted by galform. We use the glam mocks to compute the covariance matrices for the two-point correlation function and power spectrum of the LRGs and their background dark matter density field, revealing important differences. We also make predictions for the linear-growth rate and the baryon acoustic oscillations distances at z = 0.6, 0.74, and 0.93. All ‘DESI-like’ LRG catalogues are made publicly available.

It has been argued that the symmetries of gravity at null infinity should include a Diff (S²) factor associated with diffeomorphisms on the celestial sphere. However, the standard phase space of gravity does not support the action of such transformations. Building on earlier work by Laddha and one of the authors, we present an extension of the phase space of gravity at null infinity on which Diff (S²) acts canonically. The Poisson brackets of supertranslation and Diff (S²) charges reproduce the generalized BMS algebra introduced in [Campiglia and Laddha Phys. Rev. D 90, 124028 (2014), 10.1103/PhysRevD.90.124028].

The relation between early type galaxy size, surface brightness and velocity dispersion, ``the fundamental plane", has long been understood as resulting from equilibrium in their largely pressure supported stellar dynamics. The dissipation and feedback involved in reaching such an equilibrium through merger formation of these galaxies over cosmic time can be responsible for the orientation of the plane. We see a correlation between surface brightness enhancement and youth in the 6dF Galaxy Survey. Correlations of this `tilt' with stellar mass, age, concentration, shape and metallicity now point the direction for further work on the resolved kinematics and structure of these nearby galaxies and on their initial mass function and dark matter component. On the face of it, the Tully Fisher relation is a simpler one dimensional scaling relation. However, as late type galaxies have bulges as well as disks, and, as the surface density of disks is only standard for the more massive galaxies, additional parameters are involved.

We study the K ¯ p →Y K K ¯ π reactions with K ¯ =K^{¯ 0},K^- and Y =Σ⁰,Σ⁺,Λ , in the region of K K ¯ π invariant masses of 1200 -1550 MeV. The strong coupling of the f₁(1285 ) resonance to K^∗K ¯ makes the mechanism based on K^∗ exchange very efficient to produce this resonance observed in the K K ¯ π invariant mass distribution. In addition, in all these reactions one observes an associated peak at 1420 MeV which comes from the K^∗K ¯ decay mode of the f₁(1285 ) when the K^∗ is placed on shell at higher invariant masses. We call the attention to the possibility that the peaks observed in other reactions where the "f₁(1420 ) " is observed have a similar origin.

The abundance of galaxy clusters as a function of mass and redshift is a well known powerful cosmological probe, which relies on underlying modelling assumptions on the mass-observable relations (MOR). Some of the MOR parameters can be constrained directly from multi-wavelength observations, as the normalization at some reference cosmology, the mass-slope, the redshift evolution, and the intrinsic scatter. However, the cosmology dependence of MORs cannot be tested with multi-wavelength observations alone. We use magneticum simulations to explore the cosmology dependence of galaxy cluster scaling relations. We run fifteen hydrodynamical cosmological simulations varying Ω_m, Ω_b, h₀, and σ₈ (around a reference cosmological model). The MORs considered are gas mass, baryonic mass, gas temperature, Y and velocity dispersion as a function of virial mass. We verify that the mass and redshift slopes and the intrinsic scatter of the MORs are nearly independent of cosmology with variations significantly smaller than current observational uncertainties. We show that the gas mass and baryonic mass sensitively depends only on the baryon fraction, velocity dispersion, and gas temperature on h₀, and Y on both baryon fraction and h₀. We investigate the cosmological implications of our MOR parametrization on a mock catalogue created for an idealized eROSITA-like experiment. We show that our parametrization introduces a strong degeneracy between the cosmological parameters and the normalization of the MOR. Finally, the parameter constraints derived at different overdensity (Δ_500c), for X-ray bolometric gas luminosity, and for different subgrid physics prescriptions are shown in the appendix.

Several types/classes of shocks naturally arise during formation and evolution of galaxy clusters. One such class is represented by accretion shocks, associated with deceleration of infalling baryons. Such shocks, characterized by a very high Mach number, are present even in 1D models of cluster evolution. Another class is composed of 'runaway merger shocks', which appear when a merger shock, driven by a sufficiently massive infalling subcluster, propagates away from the main-cluster centre. We argue that, when the merger shock overtakes the accretion shock, a new long-living shock is formed that propagates to large distances from the main cluster (well beyond its virial radius), affecting the cold gas around the cluster. We refer to these structures as Merger-accelerated Accretion shocks (MA-shocks) in this paper. We show examples of such MA-shocks in one-dimensioanal (1D) and three-dimensional (3D) simulations and discuss their characteristic properties. In particular, (1) MA-shocks shape the boundary separating the hot intracluster medium (ICM) from the unshocked gas, giving this boundary a 'flower-like' morphology. In 3D, MA-shocks occupy space between the dense accreting filaments. (2) Evolution of MA-shocks highly depends on the Mach number of the runaway merger shock and the mass accretion rate parameter of the cluster. (3) MA-shocks may lead to the misalignment of the ICM boundary and the splashback radius.

We calculate the masses of χ_c(3 P ) states with threshold corrections in a coupled-channel model. The model was recently applied to the description of the properties of χ_c(2 P ) and χ_b(3 P ) multiplets (Ferretti and Santopinto in Phys Lett B 789:550, 2019]. We also compute the open-charm strong decay widths of the χ_c(3 P ) states and their radiative transitions. According to our predictions, the χ_c(3 P ) states should be dominated by the charmonium core, but they may also show small meson-meson components. The X(4274) is interpreted as a c c ¯ χ_{c 1}(3 P ) state. More information on the other members of the χ_c(3 P ) multiplet, as well as a more rigorous analysis of the X(4274)'s decay modes, are needed to provide further indications on the quark structure of the previous resonance.

Vector leptoquarks can address the lepton flavor universality anomalies in decays associated with the b → cℓν and b → sℓℓ transitions, as observed in recent years. While not required to explain the anomalies, these leptoquarks generically yield new sources of CP violation. In this paper, we explore constraints and discovery potential for electric dipole moments (EDMs) in leptonic and hadronic systems. We provide the most generic expressions for dipole moments induced by vector leptoquarks at one loop. We find that O(1) CP-violating phases in tau and muon couplings can lead to corresponding EDMs within reach of next-generation EDM experiments, and that existing bounds on the electron EDM already put stringent constraints on CP-violating electron couplings.

We investigate the build-up of the galactic dynamo and subsequently the origin of a magnetic driven outflow. We use a set-up of an isolated disc galaxy with a realistic circum-galactic medium (CGM). We find good agreement of the galactic dynamo with theoretical and observational predictions from the radial and toroidal components of the magnetic field as function of radius and disc scale height. We find several field reversals indicating dipole structure at early times and quadrupole structure at late times. Together with the magnetic pitch angle and the dynamo control parameters R_α, R_ω, and D, we present strong evidence for an α²-Ω dynamo. The formation of a bar in the centre leads to further amplification of the magnetic field via adiabatic compression which subsequently drives an outflow. Due to the Parker instability the magnetic field lines rise to the edge of the disc, break out, and expand freely in the CGM driven by the magnetic pressure. Finally, we investigate the correlation between magnetic field and star formation rate. Globally, we find that the magnetic field is increasing as function of the star formation rate surface density with a slope between 0.3 and 0.45 in good agreement with predictions from theory and observations. Locally, we find that the magnetic field can decrease while star formation increases. We find that this effect is correlated with the diffusion of magnetic field from the spiral arms to the interarm regions which we explicitly include by solving the induction equation and accounting for non-linear terms.

We estimate the H I mass function (HIMF) of galaxies in groups based on thousands of ALFALFA (Arecibo Legacy Fast ALFA survey) H I detections within the galaxy groups of four widely used SDSS (Sloan Digital Sky Survey) group catalogues. Although differences between the catalogues mean that there is no one definitive group galaxy HIMF, in general we find that the low-mass slope is flat, in agreement with studies based on small samples of individual groups, and that the 'knee' mass is slightly higher than that of the global HIMF of the full ALFALFA sample. We find that the observed fraction of ALFALFA galaxies in groups is approximately 22 per cent. These group galaxies were removed from the full ALFALFA source catalogue to calculate the field HIMF using the remaining galaxies. Comparison between the field and group HIMFs reveals that group galaxies make only a small contribution to the global HIMF as most ALFALFA galaxies are in the field, but beyond the HIMF 'knee' group galaxies dominate. Finally, we attempt to separate the group galaxy HIMF into bins of group halo mass, but find that too few low-mass galaxies are detected in the most massive groups to tightly constrain the slope, owing to the rarity of such groups in the nearby Universe where low-mass galaxies are detectable with existing H I surveys.

We present accurate measurements of the total H I mass in dark matter halos of different masses at z ∼ 0, by stacking the H I spectra of entire groups from the Arecibo Fast Legacy ALFA Survey. The halos are selected from the optical galaxy group catalog constructed from the Sloan Digital Sky Survey DR7 Main Galaxy sample, with reliable measurements of halo mass and halo membership. We find that the H I-halo mass relation is not a simple monotonic function, as assumed in several theoretical models. In addition to the dependence of halo mass, the total H I gas mass shows a strong dependence on the halo richness, with larger H I masses in groups with more members at fixed halo masses. Moreover, halos with at least three member galaxies in the group catalog have a sharp decrease of the H I mass, potentially caused by the virial halo shock-heating and the active galactic nucleus (AGN) feedback. The dominant contribution of the H I gas comes from the central galaxies for halos of ${M}_{{\rm{h}}}\lt {10}^{12.5}{h}^{-1}{M}_{\odot }$ , while the satellite galaxies dominate over more massive halos. Our measurements are consistent with a three-phase formation scenario of the H I-rich galaxies. The smooth cold gas accretion is driving the H I mass growth in halos of ${M}_{{\rm{h}}}\lt {10}^{11.8}{h}^{-1}{M}_{\odot }$ , with late-forming halos having more H I accreted. The virial halo shock-heating and AGN feedback will take effect to reduce the H I supply in halos of ${10}^{11.8}{h}^{-1}{M}_{\odot }\lt {M}_{{\rm{h}}}\lt {10}^{13}{h}^{-1}{M}_{\odot }$ . The H I mass in halos more massive than ${10}^{13}{h}^{-1}{M}_{\odot }$ generally grows by mergers, with the dependence on halo richness becoming much weaker.

Star-forming galaxies with strong nebular and collisional emission lines are privileged target galaxies in forthcoming cosmological large galaxy redshift surveys. We use the COSMOS2015 photometric catalogue to model galaxy spectral energy distributions and emission-line fluxes. We adopt an empirical but physically motivated model that uses information from the best-fitting spectral energy distribution of stellar continuum to each galaxy. The emission-line flux model is calibrated and validated against direct flux measurements in subsets of galaxies that have 3D-HST or zCOSMOS-Bright spectra. We take a particular care in modelling dust attenuation such that our model can explain both Hα and [O II] observed fluxes at different redshifts. We find that a simple solution to this is to introduce a redshift evolution in the dust attenuation fraction parameter, f = E_star(B - V)/E_gas(B - V), as f(z) = 0.44 + 0.2z. From this catalogue, we derive the Hα and [O II] luminosity functions up to redshifts of about 2.5 after carefully accounting for emission line flux and redshift errors. This allows us to make predictions for Hα and [O II] galaxy number counts in next-generation cosmological redshift surveys. Our modelled emission lines and spectra in the COSMOS2015 catalogue shall be useful to study the target selection for planned next-generation galaxy redshift surveys and we make them publicly available as 'EL-COSMOS' on the ASPIC data base.

Comparison of theoretical line profiles to observations provides important tests for supernova explosion models. We study the shapes of radioactive decay lines predicted by current 3D core-collapse explosion simulations, and compare these to observations of SN 1987A and Cas A. Both the widths and shifts of decay lines vary by several thousand kilometres per second depending on viewing angle. The line profiles can be complex with multiple peaks. By combining observational constraints from ⁵⁶Co decay lines, ⁴⁴Ti decay lines, and Fe IR lines, we delineate a picture of the morphology of the explosive burning ashes in SN 1987A. For M_ZAMS = 15-20 M_⊙ progenitors exploding with ∼1.5 × 10⁵¹ erg, ejecta structures suitable to reproduce the observations involve a bulk asymmetry of the ⁵⁶Ni of at least ∼400 km s^-1 and a bulk velocity of at least 1500 km s^-1. By adding constraints to reproduce the UVOIR bolometric light curve of SN 1987A up to 600 d, an ejecta mass around 14 M_⊙ is favoured. We also investigate whether observed decay lines can constrain the neutron star (NS) kick velocity. The model grid provides a constraint V_NS > V_redshift, and applying this to SN 1987A gives a NS kick of at least 500 km s^-1. For Cas A, our single model provides a satisfactory fit to the NuSTAR observations and reinforces the result that current neutrino-driven core-collapse SN models achieve enough bulk asymmetry in the explosive burning material. Finally, we investigate the internal gamma-ray field and energy deposition, and compare the 3D models to 1D approximations.

We present stellar metallicity measurements of more than 600 late-type stars in the central 10 pc of the Galactic centre. Together with our previously published KMOS data, this data set allows us to investigate, for the first time, spatial variations of the nuclear star cluster's metallicity distribution. Using the integral-field spectrograph KMOS (VLT) we observed almost half of the area enclosed by the nuclear star cluster's effective radius. We extract spectra at medium spectral resolution, and apply full spectral fitting utilising the PHOENIX library of synthetic stellar spectra. The stellar metallicities range from [M/H]=-1.25 dex to [M/H]> +0.3 dex, with most of the stars having super-solar metallicity. We are able to measure an anisotropy of the stellar metallicity distribution. In the Galactic North, the portion of sub-solar metallicity stars with [M/H]<0.0 dex is more than twice as high as in the Galactic South. One possible explanation for different fractions of sub-solar metallicity stars in different parts of the cluster is a recent merger event. We propose to test this hypothesis with high-resolution spectroscopy, and by combining the metallicity information with kinematic data.

We present the conformal freeze-in (COFI) scenario for dark matter production. At high energies, the dark sector is described by a gauge theory flowing toward a Banks-Zaks fixed point, coupled to the Standard Model via a nonrenormalizable portal interaction. In the early Universe, a nonthermal freeze-in process transfers energy from the standard model plasma to the dark sector. During the freeze-in, the dark sector is described by a strongly coupled conformal field theory. As the Universe cools, cosmological phase transitions in the Standard Model sector, either electroweak or QCD, induce conformal symmetry breaking and confinement in the dark sector. One of the resulting dark bound states is stable on the cosmological time scales and plays the role of dark matter. With the Higgs portal, the COFI scenario provides a viable dark matter candidate with mass in a phenomenologically interesting sub-MeV range. With the quark portal, a dark matter candidate with mass around 1 keV is consistent with observations. Conformal bootstrap may put a nontrivial constraint on model building in this case.

We present the analytic form of the two-loop four-graviton scattering amplitudes in Einstein gravity. To remove ultraviolet divergences we include counterterms quadratic and cubic in the Riemann curvature tensor. The two-loop numerical unitarity approach is used to deal with the challenging momentum dependence of the interactions. We exploit the algebraic properties of the integrand of the amplitude in order to reduce it to a minimal basis of Feynman integrals. Analytic expressions are obtained from numerical evaluations of the amplitude. Finally, we show that four-graviton scattering observables depend on fewer couplings than naïvely expected.

In this Letter, we investigate the effects of single derivative mixing in massive bosonic fields. In the regime of large mixing, we show that this leads to striking changes of the field dynamics, delaying the onset of classical oscillations and decreasing, or even eliminating, the friction due to Hubble expansion. We highlight this phenomenon with a few examples. In the first example, we show how an axionlike particle can have its number abundance parametrically enhanced. In the second example, we demonstrate that the QCD axion can have its number abundance enhanced allowing for misalignment driven axion dark matter all the way down to f_a of order astrophysical bounds. In the third example, we show that the delayed oscillation of the scalar field can also sustain a period of inflation. In the last example, we present a situation where an oscillating scalar field is completely frictionless and does not dilute away in time.

We review the bootstrap method for constructing six- and seven-particle amplitudes in planar $\mathcal{N}=4$ super Yang-Mills theory, by exploiting their analytic structure. We focus on two recently discovered properties which greatly simplify this construction at symbol and function level, respectively: the extended Steinmann relations, or equivalently cluster adjacency, and the coaction principle. We then demonstrate their power in determining the six-particle amplitude through six and seven loops in the NMHV and MHV sectors respectively, as well as the symbol of the NMHV seven-particle amplitude to four loops.

We present cosmological parameter measurements from the publicly available Baryon Oscillation Spectroscopic Survey (BOSS) data on anisotropic galaxy clustering in Fourier space. Compared to previous studies, our analysis has two main novel features. First, we use a complete perturbation theory model that properly takes into account the non-linear effects of dark matter clustering, short-scale physics, galaxy bias, redshift-space distortions, and large-scale bulk flows. Second, we employ a Markov-Chain Monte-Carlo technique and consistently reevaluate the full power spectrum likelihood as we scan over different cosmologies. Our baseline analysis assumes minimal ΛCDM, varies the neutrino masses within a reasonably tight range, fixes the primordial power spectrum tilt, and uses the big bang nucleosynthesis prior on the physical baryon density ω_b. In this setup, we find the following late-Universe parameters: Hubble constant H₀=(67.9± 1.1) km s^-1Mpc^-1, matter density fraction Ω_m=0.295± 0.010, and the mass fluctuation amplitude σ₈=0.721± 0.043. These parameters were measured directly from the BOSS data and independently of the Planck cosmic microwave background observations. Scanning over the power spectrum tilt or relaxing the other priors do not significantly alter our main conclusions. Finally, we discuss the information content of the BOSS power spectrum and show that it is dominated by the location of the baryon acoustic oscillations and the power spectrum shape. We argue that the contribution of the Alcock-Paczynski effect is marginal in ΛCDM, but becomes important for non-minimal cosmological models.

We perform an updated fit to LHC Higgs data and LEP electroweak precision tests in the framework of the Standard Model Effective Field Theory (SMEFT). We assume a generic structure of the SMEFT operators without imposing any flavour symmetries. The implementation is released as part of the public global SMEFT likelihood. This allows one to fit parameters of a broad class of new physics models to combined Higgs, electroweak, quark flavour, and lepton flavour observables.

In [1], two of the present authors along with P. Raman attempted to extend the Amplituhedron program for scalar field theories [2] to quartic scalar interactions. In this paper we develop various aspects of this proposal. Using recent seminal results in Representation theory [3, 4], we show that projectivity of scattering forms and existence of kinematic space associahedron completely capture planar amplitudes of quartic interaction. We generalise the results of [1] and show that for any n-particle amplitude, the positive geometry associated to the projective scattering form is a convex realisation of Stokes polytope which can be naturally embedded inside one of the ABHY associahedra defined in [2, 5]. For a special class of Stokes polytopes with hyper-cubic topology, we show that they have a canonical convex realisation in kinematic space as boundaries of kinematic space associahedra. We then use these kinematic space geometric constructions to write world-sheet forms for

It is a common belief that the last missing piece of the Standard Model of particles physics was found with the discovery of the Higgs boson at the Large Hadron Collider. However, there remains a major prediction of quantum tunnelling processes mediated by instanton solutions in the Yang-Mills theory, that is still untested in the Standard Model. The direct experimental observation of instanton-induced processes, which are a consequence of the non-trivial vacuum structure of the Standard Model and of quantum tunnelling in QFT, would be a major breakthrough in modern particle physics. In this paper, we present for the first time a full calculation of QCD instanton-induced processes in proton-proton collisions accounting for quantum corrections due to both initial and final state gluon interactions, a first implementation in an MC event generator as well as a basic strategy how to observe these effects experimentally.

We consider which is the maximum information measurable from the decay distributions of polarised baryon decays via amplitude analysis in the helicity formalism. We focus in particular on the analytical study of the $\Lambda^+_c \to pK^-\pi^+$ decay distributions, demonstrating that the full information on its decay amplitudes can be extracted from its distributions, allowing a simultaneous measurement of both helicity amplitudes and the polarisation vector. This opens the possibility to use the $\Lambda^+_c \to pK^-\pi^+$ decay for applications ranging from New Physics searches to low-energy QCD studies, in particular its use as absolute polarimeter for the $\Lambda^+_c$ baryon. This result is valid as well for baryon decays having the same spin structure and it is cross-checked numerically by means of a toy amplitude fit with Monte Carlo pseudo-data.

There are currently several existing and proposed experiments designed to probe sub-GeV dark matter (DM) using electron ionization in various materials. The projected signal rates for these experiments assume that this ionization yield arises only from DM scattering directly off electron targets, ignoring secondary ionization contributions from DM scattering off nuclear targets. We investigate the validity of this assumption and show that if sub-GeV DM couples with comparable strength to both protons and electrons, as would be the case for a dark photon mediator, the ionization signal from atomic scattering via the Migdal effect scales with the atomic number Z and 3-momentum transfer q as Z²q². The result is that the Migdal effect is always subdominant to electron scattering when the mediator is light, but that Migdal-induced ionization can dominate over electron scattering for heavy mediators and DM masses in the hundreds of MeV range. We put these two ionization processes on identical theoretical footing, address some theoretical uncertainties in the choice of atomic wave functions used to compute rates, and discuss the implications for DM scenarios where the Migdal process dominates, including for XENON10, XENON100, and the recent XENON1T results on light DM scattering.

We present an analysis of morphological, kinematic, and spectral asymmetries in observations of atomic neutral hydrogen (H I) gas from the Local Volume H I Survey (LVHIS), the VLA Imaging of Virgo in Atomic Gas (VIVA) survey, and the Hydrogen Accretion in Local Galaxies Survey. With the aim of investigating the impact of the local environment density and stellar mass on the measured H I asymmetries in future large H I surveys, we provide recommendations for the most meaningful measures of asymmetry for use in future analysis. After controlling for stellar mass, we find signs of statistically significant trends of increasing asymmetries with local density. The most significant trend we measure is for the normalized flipped spectrum residual (A_spec), with mean LVHIS and VIVA values of 0.204 ± 0.011 and 0.615 ± 0.068 at average weighted 10th nearest-neighbour galaxy number densities of log (ρ₁₀/Mpc^-3) = -1.64 and 0.88, respectively. Looking ahead to the Widefield ASKAP L-band Legacy All-sky Blind survey on the Australian Square Kilometre Array Pathfinder, we estimate that the number of detections will be sufficient to provide coverage over 5 orders of magnitude in both local density and stellar mass increasing the dynamic range and accuracy with which we can probe the effect of these properties on the asymmetry in the distribution of atomic gas in galaxies.

A complete one-loop matching calculation for real singlet scalar extensions of the Standard Model to the Standard Model effective field theory (SMEFT) of dimension- six operators is presented. We compare our analytic results obtained by using Feynman diagrams to the expressions derived in the literature by a combination of the universal one-loop effective action (UOLEA) approach and Feynman calculus. After identifying contributions that have been overlooked in the existing calculations, we find that the pure diagrammatic approach and the mixed method lead to identical results. We highlight some of the subtleties involved in computing one-loop matching corrections in SMEFT.

Aims: The goal of this study is to present the development of a machine learning based approach that utilizes phase space alone to separate the Gaia DR2 stars into two categories: those accreted onto the Milky Way from those that are in situ. Traditional selection methods that have been used to identify accreted stars typically rely on full 3D velocity, metallicity information, or both, which significantly reduces the number of classifiable stars. The approach advocated here is applicable to a much larger portion of Gaia DR2.
Methods: A method known as "transfer learning" is shown to be effective through extensive testing on a set of mock Gaia catalogs that are based on the FIRE cosmological zoom-in hydrodynamic simulations of Milky Way-mass galaxies. The machine is first trained on simulated data using only 5D kinematics as inputs and is then further trained on a cross-matched Gaia/RAVE data set, which improves sensitivity to properties of the real Milky Way.
Results: The result is a catalog that identifies ∼767 000 accreted stars within Gaia DR2. This catalog can yield empirical insights into the merger history of the Milky Way and could be used to infer properties of the dark matter distribution.

Following the recent analysis done in collaboration with Jason Aebischer and Christoph Bobeth, I summarize the optimal, in our view, strategy for the present evaluation of the ratio ɛ ^‧/ɛ in the Standard Model. In particular, I emphasize the importance of the correct matching of the long-distance and short-distance contributions to ɛ ^‧/ɛ, which presently is only achieved by RBC-UKQCD lattice QCD collaboration and by the analytical Dual QCD approach. An important role play also the isospin-breaking and QED effects, which presently are best known from chiral perturbation theory, albeit still with a significant error. Finally, it is essential to include NNLO QCD corrections in order to reduce unphysical renormalization scheme and scale dependences present at the NLO level. Here µ _c in m _c (µ _c ) in the case of QCD penguin contributions and µ _t in m _t (µ _t ) in the case of electroweak penguin contributions play the most important roles. Presently the error on ɛ ^‧/ɛ is dominated by the uncertainties in the QCDP parameter B_6^(1/2) and the isospin-breaking parameter \hat Ω _{{eff}}. We present a table illustrating this.

We investigate the stellar kinematics of a sample of galaxies extracted from the hydrodynamic cosmological Magneticum Pathfinder simulations out to five half-mass radii. We construct differential radial stellar spin profiles quantified by the observationally widely used λ and the closely related (V/σ) parameters. We find three characteristic profile shapes: profiles exhibiting a (I) peak within 2.5 half-mass radii and a subsequent decrease; (II) continuous increase that plateaus at larger radii typically with a high amplitude; (III) completely flat behaviour typically with low amplitude, in agreement with observations. This shows that the kinematic state of the stellar component can vary significantly with radius, suggesting a distinct interplay between in-situ star formation and ex-situ accretion of stars. Following the evolution of our sample through time, we provide evidence that the accretion history of galaxies with decreasing profiles is dominated by the anisotropic accretion of low-mass satellites that get disrupted beyond ∼2.0 half-mass radii, building up a stellar halo with non-ordered motion while maintaining the central rotation already present at z = 2. In fact, at z = 2 decreasing profiles are the predominant profile class. Hence, we can predict a distinct formation pathway for galaxies with a decreasing profile and show that the centre resembles an old embedded disc. Furthermore, we show that the radius of the kinematic transition provides a good estimation for the transition radius from in-situ stars in the centre to accreted stars in the halo.

If dark matter was produced in the early Universe by the decoupling of its annihilations into known particles, there is a sharp experimental target for the size of its coupling. We show that if dark matter was produced by inelastic scattering against a lighter particle from the thermal bath, then its coupling can be exponentially smaller than the coupling required for its production from annihilations. As an application, we demonstrate that dark matter produced by inelastic scattering against electrons provides new thermal relic targets for direct detection and fixed target experiments.

The baryon acoustic oscillations feature (BAO) imprinted in the clustering correlation function is known to furnish us cosmic distance determinations that are independent of the cosmological-background model and the primordial perturbation parameters. These measurements can be accomplished rigorously by means of the purely geometric BAO methods. To date two different purely geometric BAO approaches have been proposed. The first exploits the linear-point standard ruler. The second, called correlation-function model-fitting, exploits the sound-horizon standard ruler. A key difference between them is that, when estimated from clustering data, the linear point makes use of a cosmological-model-independent procedure to extract the ratio of the ruler to the cosmic distance, while the correlation-function model-fitting relies on a phenomenological cosmological model for the correlation function. Nevertheless the two rulers need to be precisely defined independently of any specific observable (e.g., the BAO). We define the linear point and sound horizon and we fully characterize and compare the two rulers' cosmological-parameter dependence. We find that they are both geometrical (i.e., independent of the primordial cosmological parameters) within the required accuracy, and that they have the same parameter dependence for a wide range of parameter values. We estimate the rulers' best-fit values and errors, given the cosmological constraints obtained by the Planck Satellite team from their measurements of the cosmic microwave background temperature and polarization anisotropies. We do this for three different cosmological models encompassed by the purely geometric BAO methods. In each case we find that the relative errors of the two rulers coincide and they are insensitive to the assumed cosmological model. Interestingly both the linear point and the sound horizon shift by 0.5 σ when we do not fix the spatial geometry to be flat in Λ CDM . This points toward a sensitivity of the rulers to different cosmological models when they are estimated from the cosmic microwave background.

The quality of the recent GlueX J /ψ photoproduction data from Hall D at Jefferson Laboratory and the proximity of the data to the energy threshold, gives access to a variety of interesting physics aspects. As an example, an estimation of the J /ψ -nucleon scattering length α_{J /ψ p} is provided within the vector meson dominance model. It results in | α_{J /ψ p}|=(3.08 ±0.55 (stat . ) ±0.42 (syst . ) ) mfm which is much smaller than a typical size of a hadron.

Building on Weinberg's approach to effective field theory for inflation, we construct an effective Lagrangian for a pseudo scalar (axion) inflaton field with shift symmetry. In this Lagrangian we allow the axion field to couple to non-Abelian gauge fields via a Chern-Simons term. We then analyze a class of inflation models driven by kinetic terms. We find that the observational constraints on the amplitudes of curvature perturbations and non-Gaussianity yield a lower bound for the tensor-to-scalar ratio of $r\gtrsim 5\times 10^{-3}$ from the vacuum fluctuation. The sourced gravitational wave from SU(2) gauge fields further increases the tensor-to-scalar ratio and makes the total gravitational wave partially chiral and non-Gaussian, which can be probed by polarization of the cosmic microwave background and direct detection experiments. We discuss constraints on parameter space due to backreaction of spin-2 particles produced by the gauge field.

We have studied the small-scale distribution of atomic hydrogen (H I) using 21 cm absorption spectra against multiple-component background radio continuum sources from the 21-SPONGE survey and the Millennium Arecibo Absorption-Line Survey. We have found >5σ optical depth variations at a level of ∼0.03-0.5 between 13 out of 14 adjacent sightlines separated by a few arcseconds to a few arcminutes, suggesting the presence of neutral structures on spatial scales from a few to thousands of au (which we refer to as tiny-scale atomic structure, TSAS). The optical depth variations are strongest in directions where the H I column density and the fraction of H I in the cold neutral medium (CNM) are highest, which tend to be at low Galactic latitudes. By measuring changes in the properties of Gaussian components fitted to the absorption spectra, we find that changes in both the peak optical depth and the linewidth of TSAS absorption features contribute to the observed optical depth variations, while changes in the central velocity do not appear to strongly impact the observed variations. Both thermal and turbulent motions contribute appreciably to the linewidths, but the turbulence does not appear strong enough to confine overpressured TSAS. In a majority of cases, the TSAS column densities are sufficiently high that these structures can radiatively cool fast enough to maintain thermal equilibrium with their surroundings, even if they are overpressured. We also find that a majority of TSAS is associated with the CNM. For TSAS in the direction of the Taurus molecular cloud and the local Leo cold cloud, we estimate densities over an order of magnitude higher than typical CNM densities.

We examine the contribution of small instantons to the axion mass in various UV completions of QCD. We show that the reason behind the potential dominance of such contributions is the non-trivial embedding of QCD into the UV theory. The effects from instantons in the partially broken gauge group appear as "fractional instanton" corrections in the effective theory. These will exhibit unusual dependences on the various scales in the problem whenever the index of embedding is non-trivial. We present a full one-instanton calculation of the axion mass in the simplest product group models, carefully keeping track of numerical prefactors. Rather than using a 't Hooft operator approximation we directly evaluate the contributions to the vacuum bubble, automatically capturing the effects of closing up external fermion lines with Higgs loops. This approach is manifestly finite and removes the uncertainty associated with introducing a cutoff scale for the Higgs loops. We verify that the small instantons may dominate over the QCD contribution for very high breaking scales and at least three group factors.

Polarizations of primordial gravitational waves can be relevant when considering inflationary universe in modified gravity or when matter fields survive during inflation. Such polarizations have been discussed in the Bunch-Davies vacuum. Instead of taking into account dynamical generation of polarizations of gravitational waves, in this paper, we consider polarized initial states constructed from $SU(2)$ coherent states. We then evaluate the power spectrums of the primordial gravitational waves in the states.

New Physics can manifest itself in kinematic distributions of particle decays. The parameter space defining the shape of such distributions can be large which is chalenging for both theoretical and experimental studies. Using clustering algorithms, the parameter space can however be dissected into subsets (clusters) which correspond to similar kinematic distributions. Clusters can then be represented by benchmark points, which allow for less involved studies and a concise presentation of the results. We demonstrate this concept using the Python package ClusterKinG, an easy to use framework for the clustering of distributions that particularly aims to make these techniques more accessible in a High Energy Physics context. As an example we consider B ¯→D^(∗)τ^-ν_¯τ distributions and discuss various clustering methods and possible implications for future experimental analyses.

In this work, we study how the dust coagulation/fragmentation will influence the evolution and observational appearances of vortices induced by a massive planet embedded in a low-viscosity disk by performing global 2D high-resolution hydrodynamical simulations. Within the vortex, due to its higher gas surface density and steeper pressure gradients, dust coagulation, fragmentation, and drift (to the vortex center) are all quite efficient, producing dust particles ranging from 1 μm to ∼1.0 cm, as well as an overall high dust-to-gas ratio (above unity). In addition, the dust size distribution is quite nonuniform inside the vortex, with the mass-weighted average dust size at the vortex center (∼4.0 mm) being a factor of ∼10 larger than other vortex regions. Both large (∼millimeter) and small (tens of microns) particles contribute strongly to affect the gas motion within the vortex. As such, we find that the inclusion of dust coagulation has a significant impact on the vortex lifetime and the typical vortex lifetime is about 1000 orbits. After the initial gaseous vortex is destroyed, the dust spreads into a ring with a few remaining smaller gaseous vortices with a high dust concentration and a large maximum size (∼millimeter). At late time, the synthetic dust continuum images for the coagulation case show as a ring inlaid with several hot spots at the 1.33 mm band, while only distinct hot spots remain at 7.0 mm.

The chemical composition of planets is determined by the distribution of the various molecular species in the protoplanetary disk at the time of their formation. To date, only a handful of disks have been imaged in multiple spectral lines with high spatial resolution. As part of a small campaign devoted to the chemical characterization of disk-outflow sources in Taurus, we report on new ALMA Band 6 (~1.3 mm) observations with ~0.15'' (20 au) resolution toward the embedded young star DG Tau B. Images of the continuum emission reveals a dust disk with rings and, putatively, a leading spiral arm. The disk, as well as the prominent outflow cavities, are detected in CO, H₂CO, CS, and CN; instead, they remain undetected in SO₂, HDO, and CH₃OH. From the absorption of the back-side outflow, we inferred that the disk emission is optically thick in the inner 50 au. This morphology explains why no line emission is detected from this inner region and poses some limitations toward the calculation of the dust mass and the characterization of the inner gaseous disk. The H₂CO and CS emission from the inner 200 au is mostly from the disk, and their morphology is very similar. The CN emission significantly differs from the other two molecules as it is observed only beyond 150 au. This ring-like morphology is consistent with previous observations and the predictions of thermochemical disk models. Finally, we constrained the disk-integrated column density of all molecules. In particular, we found that the CH₃OH/H₂CO ratio must be smaller than ~2, making the methanol non-detection still consistent with the only such ratio available from the literature (1.27 in TW Hya).

The reduced datacubes are only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/636/A65

We study the Schrödinger-Poisson (SP) method in the context of cosmological large-scale structure formation in an expanding background. In the limit ℏ→0, the SP technique can be viewed as an effective method to sample the phase space distribution of cold dark matter that remains valid on non-linear scales. We present results for the 2D and 3D matter correlation function and power spectrum at length scales corresponding to the baryon acoustic oscillation (BAO) peak. We discuss systematic effects of the SP method applied to cold dark matter and explore how they depend on the simulation parameters. In particular, we identify a combination of simulation parameters that controls the scale-independent loss of power observed at low redshifts, and discuss the scale relevant to this effect.

We carry out a comprehensive analysis of the full set of B¯q→D(∗)q form factors for spectator quarks q=u,d,s within the framework of the Heavy-Quark Expansion (HQE) to order O(αs,1/mb,1/m2c). In addition to the available lattice QCD calculations we make use of two new sets of theoretical constraints: we produce for the first time numerical predictions for the full set of B¯s→D(∗)s form factors using Light-Cone Sum Rules with Bs-meson distribution amplitudes. Furthermore, we reassess the QCD three-point sum rule results for the Isgur-Wise functions entering all our form factors for both q=u,d and q=s spectator quarks. These additional constraints allow us to go beyond the commonly used assumption of SU(3)F symmetry for the B¯s→D(∗)s form factors, especially in the unitarity constraints which we impose throughout our analysis. We find the coefficients of the IW functions emerging at O(1/m2c) to be consistent with the naive O(1) expectation, indicating a good convergence of the HQE. While we do not find significant SU(3) breaking, the explicit treatment of q=s as compared to a simple symmetry assumption renders the unitarity constraints more effective. We find that the (pseudo)scalar bounds are saturated to a large degree, which affects our theory predictions. We analyze the phenomenological consequences of our improved form factors by extracting |Vcb| from B¯→D(∗)ℓν decays and producing theoretical predictions for the lepton-flavour universality ratios R(D), R(D∗), R(Ds) and R(D∗s), as well as the τ- and D∗q polarization fractions for the B¯q→D(∗)qτν modes.

All life on Earth is built of organic molecules, so the primordial sources of reduced carbon remain a major open question in studies of the origin of life. A variant of the alkaline-hydrothermal-vent theory for life’s emergence suggests that organics could have been produced by the reduction of CO2 via H2 oxidation, facilitated by geologically sustained pH gradients. The process would be an abiotic analog—and proposed evolutionary predecessor—of the Wood–Ljungdahl acetyl-CoA pathway of modern archaea and bacteria. The first energetic bottleneck of the pathway involves the endergonic reduction of CO2 with H2 to formate (HCOO–), which has proven elusive in mild abiotic settings. Here we show the reduction of CO2 with H2 at room temperature under moderate pressures (1.5 bar), driven by microfluidic pH gradients across inorganic Fe(Ni)S precipitates. Isotopic labeling with 13C confirmed formate production. Separately, deuterium (2H) labeling indicated that electron transfer to CO2 does not occur via direct hydrogenation with H2 but instead, freshly deposited Fe(Ni)S precipitates appear to facilitate electron transfer in an electrochemical-cell mechanism with two distinct half-reactions. Decreasing the pH gradient significantly, removing H2, or eliminating the precipitate yielded no detectable product. Our work demonstrates the feasibility of spatially separated yet electrically coupled geochemical reactions as drivers of otherwise endergonic processes. Beyond corroborating the ability of early-Earth alkaline hydrothermal systems to couple carbon reduction to hydrogen oxidation through biologically relevant mechanisms, these results may also be of significance for industrial and environmental applications, where other redox reactions could be facilitated using similarly mild approaches.

The forthcoming generation of galaxy redshift surveys will sample the large-scale structure of the Universe over unprecedented volumes with high-density tracers. This advancement will make robust measurements of three-point clustering statistics possible. In preparation for this improvement, we investigate how several methodological choices can influence inferences based on the bispectrum about galaxy bias and shot noise. We first measure the real-space bispectrum of dark-matter haloes extracted from 298 N-body simulations covering a volume of approximately 1000 Gpc³. We then fit a series of theoretical models based on tree-level perturbation theory to the numerical data. To achieve this, we estimate the covariance matrix of the measurement errors by using 10,000 mock catalogues generated with the PINOCCHIO code. We study how the model constraints are influenced by the binning strategy for the bispectrum configurations and by the form of the likelihood function. We also use Bayesian model-selection techniques to single out the optimal theoretical description of our data. We find that a three-parameter bias model combined with Poissonian shot noise is necessary to model the halo bispectrum up to scales of k_maxlesssim 0.08 Mpc^-1, although fitting formulae that relate the bias parameters can be helpful to reduce the freedom of the model without compromising accuracy. Our data clearly disfavour local Eulerian and local Lagrangian bias models and do not require corrections to Poissonian shot noise. We anticipate that model-selection diagnostics will be particularly useful to extend the analysis to smaller scales as, in this case, the number of model parameters will grow significantly large.

Context. X-ray- and extreme ultraviolet (XEUV) driven photoevaporative winds acting on protoplanetary disks around young T Tauri stars may crucially impact disk evolution, affecting both gas and dust distributions.
Aims: We investigate the dust entrainment in XEUV-driven photoevaporative winds and compare our results to existing magnetohydrodynamic and EUV-only models.
Methods: We used a 2D hydrodynamical gas model of a protoplanetary disk irradiated by both X-ray and EUV spectra from a central T Tauri star to trace the motion of passive Lagrangian dust grains of various sizes. The trajectories were modelled starting at the disk surface in order to investigate dust entrainment in the wind.
Results: For an X-ray luminosity of L_X = 2 × 10³⁰ erg s^-1 emitted by a M_* = 0.7 M_⊙ star, corresponding to a wind mass-loss rate of Ṁ_w ≃ 2.6 × 10^-8 M_⊙ yr^-1, we find dust entrainment for sizes a₀ ≲ 11 μm (9 μm) from the inner 25 AU (120 AU). This is an enhancement over dust entrainment in less vigorous EUV-driven winds with Ṁ_w ≃ 10^-10 M_⊙ yr^-1. Our numerical model also shows deviations of dust grain trajectories from the gas streamlines even for μm-sized particles. In addition, we find a correlation between the size of the entrained grains and the maximum height they reach in the outflow.
Conclusions: X-ray-driven photoevaporative winds are expected to be dust-rich if small grains are present in the disk atmosphere.

We calculate a new contribution to the axion mass that arises from gluons propagating in a 5th dimension at high energies. By uplifting the 4D instanton solution to five dimensions, the positive frequency modes of the Kaluza-Klein states generate a power-law term in the effective action that inversely grows with the instanton size. This causes 5D small instantons to enhance the axion mass in a way that does not spoil the axion solution to the strong CP problem. Moreover this enhancement can be much larger than the usual QCD contribution from large instantons, although it requires the 5D gauge theory to be near the non-perturbative limit. Thus our result suggests that the mass range of axions (or axion-like particles), which is important for ongoing experimental searches, can depend sensitively on the UV modification of QCD.

QCD exhibits complex dynamics near S-wave two-body thresholds. For light mesons, we see this in the failure of quark models to explain the f₀ (500) and K₀^* (700) masses. For charmonium, an unexpected X (3872) state appears at the open charm threshold. In heavy-light systems, analogous threshold effects appear for the lowest J^P =0⁺ and 1⁺ states in the D_s and B_s systems. Here we describe how lattice QCD can be used to understand these threshold dynamics by smoothly varying the strange-quark mass when studying the heavy-light systems. Small perturbations around the physical strange quark mass are used so to always remain near the physical QCD dynamics. This calculation is a straightforward extension of those already in the literature and can be undertaken by multiple lattice QCD collaborations with minimal computational cost.

Inelastic dark matter and strongly interacting dark matter are poorly constrained by direct detection experiments since they both require the scattering event to deliver energy from the nucleus into the dark matter in order to have observable effects. We propose to test these scenarios by searching for the collisional deexcitation of metastable nuclear isomers by the dark matter particles. The longevity of these isomers is related to a strong suppression of γ - and β -transitions, typically inhibited by a large difference in the angular momentum for the nuclear transition. The collisional deexcitation by dark matter is possible since heavy dark matter particles can have a momentum exchange with the nucleus comparable to the inverse nuclear size, hence lifting tremendous angular momentum suppression of the nuclear transition. This deexcitation can be observed either by searching for the direct effects of the decaying isomer, or through the rescattering or decay of excited dark matter states in a nearby conventional dark matter detector setup. Existing nuclear isomer sources such as naturally occurring ^Tam₁₈₀ , ^Bam₁₃₇ produced in decaying Cesium in nuclear waste, ^Lum₁₇₇ from medical waste, and ^Hfm₁₇₈ from the Department of Energy storage can be combined with current dark matter detector technology to search for this class of dark matter.

Context. Complex organic molecules (COMs) have been detected in a few Class 0 protostars but their origin is not well understood. While the usual picture of a hot corino explains their presence as resulting from the heating of the inner envelope by the nascent protostar, shocks in the outflow, disk wind, the presence of a flared disk, or the interaction region between envelope and disk at the centrifugal barrier have also been claimed to enhance the abundance of COMs.
Aims: Going beyond studies of individual objects, we want to investigate the origin of COMs in young protostars on a statistical basis.
Methods: We use the CALYPSO survey performed with the Plateau de Bure Interferometer of the Institut de Radioastronomie Millimétrique to search for COMs at high angular resolution in a sample of 26 solar-type protostars, including 22 Class 0 and four Class I objects. We derive the column densities of the detected molecules under the local thermodynamic equilibrium approximation and search for correlations between their abundances and with various source properties.
Results: Methanol is detected in 12 sources and tentatively in one source, which represents half of the sample. Eight sources (30%) have detections of at least three COMs. We find a strong chemical differentiation in multiple systems with five systems having one component with at least three COMs detected but the other component devoid of COM emission. All sources with a luminosity higher than 4 L_⊙ have at least one detected COM whereas no COM emission is detected in sources with internal luminosity lower than 2 L_⊙, likely because of a lack of sensitivity. Internal luminosity is found to be the source parameter impacting the COM chemical composition of the sources the most, while there is no obvious correlation between the detection of COM emission and that of a disk-like structure. A canonical hot-corino origin may explain the COM emission in four sources, an accretion-shock origin in two or possibly three sources, and an outflow origin in three sources. The CALYPSO sources with COM detections can be classified into three groups on the basis of the abundances of oxygen-bearing molecules, cyanides, and CHO-bearing molecules. These chemical groups correlate neither with the COM origin scenarios, nor with the evolutionary status of the sources if we take the ratio of envelope mass to internal luminosity as an evolutionary tracer. We find strong correlations between molecules that are a priori not related chemically (for instance methanol and methyl cyanide), implying that the existence of a correlation does not imply a chemical link.
Conclusions: The CALYPSO survey has revealed a chemical differentiation in multiple systems that is markedly different from the case of the prototypical binary IRAS 16293-2422. This raises the question of whether all low-mass protostars go through a phase showing COM emission. A larger sample of young protostars and a more accurate determination of their internal luminosity will be necessary to make further progress. Searching for correlations between the COM emission and the jet/outflow properties of the sources may also be promising.

Based on observations carried out with the IRAM Plateau de Bure Interferometer. IRAM is supported by INSU/CNRS (France), MPG (Germany), and IGN (Spain).

The CALYPSO calibrated visibility tables and maps are publicly available at http://www.iram-institute.org/EN/content-page-317-7-158-240-317-0.html

We consider a scenario where the dark sector includes two Feebly Interacting Massive Particles (FIMPs), with couplings to the Standard Model particles that allow their production in the Early Universe via thermal freeze-in. These couplings generically lead to the decay of the heavier dark matter component into the lighter, possibly leading to observable signals of the otherwise elusive FIMPs. Concretely, we argue that the loop induced decay ψ_2→ψ1γ for fermionic FIMPs, or phi_2→phi1γγ for scalar FIMPs, could have detectable rates for model parameters compatible with the observed dark matter abundance.

Context. The water snow line divides dry and icy solid material in protoplanetary disks. It has been thought to significantly affect planet formation at all stages. If dry particles break up more easily than icy ones, then the snow line causes a traffic jam because small grains drift inward at lower speeds than larger pebbles.
Aims: We aim to evaluate the effect of high dust concentrations around the snow line onto the gas dynamics.
Methods: Using numerical simulations, we modeled the global radial evolution of an axisymmetric protoplanetary disk. Our model includes particle growth, the evaporation and recondensation of water, and the back-reaction of dust onto the gas. The model takes into account the vertical distribution of dust particles.
Results: We find that the dust back-reaction can stop and even reverse the net flux of gas outside the snow line, decreasing the gas accretion rate onto the star to under 50% of its initial value. At the same time, the dust accumulates at the snow line, reaching dust-to-gas ratios of ɛ ≳ 0.8, and it delivers large amounts of water vapor towards the inner disk as the icy particles cross the snowline. However, the accumulation of dust at the snow line and the decrease in the gas accretion rate only take place if the global dust-to-gas ratio is high (ɛ₀ ≳ 0.03), the viscous turbulence is low (α_ν ≲ 10^-3), the disk is large enough (r_c ≳ 100 au), and only during the early phases of the disk evolution (t ≲ 1 Myr). Otherwise the dust back-reaction fails to perturb the gas motion.

We study radial oscillations of non-rotating neutron stars (NSs) in four-dimensional general relativity. The interior of the NS was modeled within a recently proposed multicomponent realistic equation of state (EoS) with the induced surface tension (IST). In particular, we considered the IST EoS with two sets of model parameters, that both reproduce all the known properties of normal nuclear matter, give a high quality description of the proton flow constraint, hadron multiplicities created in nuclear-nuclear collisions, consistent with astrophysical observations and the observational data from the NS-NS merger. We computed the 12 lowest radial oscillation modes, their frequencies and corresponding eigenfunctions, as well as the large frequency separation for six selected fiducial NSs (with different radii and masses of 1.2, 1.5 and 1.9 solar masses) of the two distinct model sets. The calculated frequencies show their continuous growth with an increase of the NS central baryon density. Moreover, we found correlations between the behavior of the first eigenfunction calculated for the fundamental mode, the adiabatic index and the speed of sound profile, which could be used to probe the internal structure of NSs with the asteroseismology data.

We predict magnitudes for young planets embedded in transition discs, still affected by extinction due to material in the disc. We focus on Jupiter-sized planets at a late stage of their formation, when the planet has carved a deep gap in the gas and dust distributions and the disc starts to being transparent to the planet flux in the infrared (IR). Column densities are estimated by means of three-dimensional hydrodynamical models, performed for several planet masses. Expected magnitudes are obtained by using typical extinction properties of the disc material and evolutionary models of giant planets. For the simulated cases located at 5.2 au in a disc with a local unperturbed surface density of 127 g cm^{-2}, a 1M_J planet is highly extinct in the J, H, and Kbands, with predicted absolute magnitudes ≥ 50 mag. In the L and Mbands, extinction decreases, with planet magnitudes between 25 and 35 mag. In the Nband, due to the silicate feature on the dust opacities, the expected magnitude increases to ∼40 mag. For a 2M_J planet, the magnitudes in the J, H, and Kbands are above 22 mag, while for the L, M, and Nbands, the planet magnitudes are between 15 and 20 mag. For the 5M_J planet, extinction does not play a role in any IR band, due to its ability to open deep gaps. Contrast curves are derived for the transition discs in CQ Tau, PDS 70, HL Tau, TW Hya, and HD 163296. Planet mass upper limits are estimated for the known gaps in the last two systems.

We present the novel algorithmically regularized integration method MSTAR for high-accuracy (|ΔE/E| ≳ 10^-14) integrations of N-body systems using minimum spanning tree coordinates. The twofold parallelization of the O(N_part^2) force loops and the substep divisions of the extrapolation method allow for a parallel scaling up to N_CPU = 0.2 × N_part. The efficient parallel scaling of MSTAR makes the accurate integration of much larger particle numbers possible compared to the traditional algorithmic regularization chain (AR-CHAIN) methods, e.g. N_part = 5000 particles on 400 CPUs for 1 Gyr in a few weeks of wall-clock time. We present applications of MSTAR on few particle systems, studying the Kozai mechanism and N-body systems like star clusters with up to N_part = 10⁴ particles. Combined with a tree or fast multipole-based integrator, the high performance of MSTAR removes a major computational bottleneck in simulations with regularized subsystems. It will enable the next-generation galactic-scale simulations with up to 10⁹ stellar particles (e.g. m_\star = 100 M_⊙ for an M_\star = 10^{11} M_⊙ galaxy), including accurate collisional dynamics in the vicinity of nuclear supermassive black holes.

We present a statistical analysis of the optical properties of an X-ray-selected Type 1 active galactic nucleus (AGN) sample, using high signal-to-noise ratio (S/N>20) spectra of the counterparts of the ROSAT/2RXS sources in the footprint of the SDSS-IV/SPIDERS (Spectroscopic IDentification of eROSITA Sources) programme. The final sample contains 2100 sources. It significantly extends the redshift and luminosity ranges (z ∼ 0.01-0.80 and L_{0.1-2.4 keV} ∼ 2.0 × 10^{41}-1.0 × 10^{46} erg s^{-1}) used so far in this kind of analysis. By means of a principal component analysis, we derive eigenvector (EV) 1 and 2 in an eleven-dimensional optical and X-ray parameter space, which are consistent with previous results. The validity of the correlations of the Eddington ratio L/L_Edd with EV1 and the black hole mass with EV2 is strongly confirmed. These results imply that L/L_Edd and black hole mass are related to the diversity of the optical properties of Type 1 AGNs. Investigating the relation of the width and asymmetry of H β and the relative strength of the iron emission r_{Fe II}, we show that our analysis supports the presence of a distinct kinematic region: the very broad line region. Furthermore, comparing sources with a red-asymmetric broad H β emission line to sources for which it is blue asymmetric, we find an intriguing difference in the correlation of the Fe II and the continuum emission strengths. We show that this contrasting behaviour is consistent with a flattened, stratified model of the broad-line region, in which the Fe II-emitting region is shielded from the central source.

The inner parsec of our Galaxy contains tens of Wolf-Rayet stars whose powerful outflows are constantly interacting while filling the region with hot, diffuse plasma. Theoretical models have shown that, in some cases, the collision of stellar winds can generate cold, dense material in the form of clumps. However, their formation process and properties are not well understood yet. In this work, we present, for the first time, a statistical study of the clump formation process in unstable wind collisions. We study systems with dense outflows (∼ 10^{-5} M_{⊙ } yr^{-1}), wind speeds of 500-1500 km s^{-1}, and stellar separations of ∼20-200 au. We develop three-dimensional high-resolution hydrodynamical simulations of stellar wind collisions with the adaptive-mesh refinement grid-based code RAMSES. We aim at characterizing the initial properties of clumps that form through hydrodynamic instabilities, mostly via the non-linear thin-shell instability (NTSI). Our results confirm that more massive clumps are formed in systems whose winds are close to the transition between the radiative and adiabatic regimes. Increasing either the wind speed or the degree of asymmetry increases the dispersion of the clump mass and ejection speed distributions. Nevertheless, the most massive clumps are very light (∼10^-3-10^{-2} M_{\oplus }), about three orders of magnitude less massive than theoretical upper limits. Applying these results to the Galactic Centre, we find that clumps formed through the NTSI should not be heavy enough either to affect the thermodynamic state of the region or to survive for long enough to fall on to the central supermassive black hole.

It has been speculated for a long time that neutrinos from a supernova (SN) may undergo fast flavor conversions near the collapsed stellar core. We perform a detailed study of this intriguing possibility, for the first time analyzing two time-dependent state-of-the-art three-dimensional (3D) SN models of 9 M_⊙ and 20 M_⊙ from recent papers of Glas et al. Both models were computed with multidimensional three-flavor neutrino transport based on a two-moment solver, and both exhibit the presence of the so-called lepton-number emission self-sustained asymmetry (LESA). The transport solution does not provide the angular distributions of the flavor-dependent neutrino fluxes, which are crucial to track the fast flavor instability. To overcome this limitation, we use a recently proposed approach based on the angular moments of the energy-integrated electron lepton-number distribution up to second order, i.e., angle-energy integrals of the difference between ν_e and ν_¯e phase-space distributions multiplied by corresponding powers of the unit vector of the neutrino velocity. With this method we find the possibility of fast neutrino flavor instability at radii smaller than ∼20 km , which is well interior to the neutrinosphere where neutrinos are still in the diffusive and near-equilibrium regime. Our results confirm recent observations in a two-dimensional (2D) (axisymmetric) SN model and in 2D and 3D models with a fixed matter background, which were computed with Boltzmann neutrino transport. However, the flavor unstable locations are not isolated points as discussed previously, but thin skins surrounding volumes where ν_¯e are more abundant than ν_e. These volumes grow with time and appear first in the convective layer of the proto-neutron star (PNS), where a decreasing electron fraction and high temperatures favor the occurrence of regions with negative neutrino chemical potential. Since the electron fraction remains higher in the LESA dipole direction, where convective lepton-number transport out from the nonconvective PNS core slows down the deleptonization, flavor unstable conditions become more widespread in the opposite hemisphere. This interesting phenomenon deserves further investigation, since its impact on SN modeling and possible consequences for SN dynamics and neutrino observations are presently unclear.

Type Ic supernovae (SNe Ic) are a sub-class of core-collapse SNe that exhibit no helium or hydrogen lines in their spectra. Their progenitors are thought to be bare carbon-oxygen cores formed during the evolution of massive stars that are stripped of their hydrogen and helium envelopes sometime before collapse. SNe Ic present a range of luminosities and spectral properties, from luminous GRB-SNe with broad-lined spectra to less luminous events with narrow-line spectra. Modelling SNe Ic reveals a wide range of both kinetic energies, ejecta masses, and ⁵⁶Ni masses. To explore this diversity and how it comes about, light curves and spectra are computed from the ejecta following the explosion of an initially 22 M_⊙ progenitor that was artificially stripped of its hydrogen and helium shells, producing a bare CO core of ∼5 M_⊙, resulting in an ejected mass of ∼4 M_⊙, which is an average value for SNe Ic. Four different explosion energies are used that cover a range of observed SNe. Finally, ⁵⁶Ni and other elements are artificially mixed in the ejecta using two approximations to determine how element distribution affects light curves and spectra. The combination of different explosion energy and degree of mixing produces spectra that roughly replicate the distribution of near-peak spectroscopic features of SNe Ic. High explosion energies combined with extensive mixing can produce red, broad-lined spectra, while minimal mixing and a lower explosion energy produce bluer, narrow-lined spectra.

We construct an emulator for the halo mass function over group and cluster mass scales for a range of cosmologies, including the effects of dynamical dark energy and massive neutrinos. The emulator is based on the recently completed Mira-Titan Universe suite of cosmological N-body simulations. The main set of simulations spans 111 cosmological models with 2.1 Gpc boxes. We extract halo catalogs in the redshift range z = [0.0, 2.0] and for masses . The emulator covers an eight-dimensional hypercube spanned by {, , , σ 8, h, n s , w 0, w a }; spatial flatness is assumed. We obtain smooth halo mass functions by fitting piecewise second-order polynomials to the halo catalogs and employ Gaussian process regression to construct the emulator while keeping track of the statistical noise in the input halo catalogs and uncertainties in the regression process. For redshifts z ≲ 1, the typical emulator precision is better than 2% for and <10% for . For comparison, fitting functions using the traditional universal form for the halo mass function can be biased at up to 30% at for z = 0. Our emulator is publicly available at github.com/SebastianBocquet/MiraTitanHMFemulator.

Bimetric theory describes a massless and a massive spin-2 field with fully non-linear (self-)interactions. It has a rich phenomenology and has been successfully tested with several data sets. However, the observational constraints have not been combined in a consistent framework, yet. We propose a parametrization of bimetric solutions in terms of the effective cosmological constant Λ and the mass mFP of the spin-2 field as well as its coupling strength to ordinary matter &baralpha;. This simplifies choosing priors in statistical analysis and allows to directly constrain these parameters with observational data not only from local systems but also from cosmology. By identifying the physical vacuum of bimetric theory these parameters are uniquely determined. We work out the new parametrization for various submodels and present the implied consistency constraints on the physical parameter space. As an application we derive observational constraints from SN1a on the physical parameters. We find that a large portion of the physical parameter space is in perfect agreement with current supernova data including self-accelerating models with a heavy spin-2 field.

We construct and validate the selection function of the MARD-Y3 galaxy cluster sample. This sample was selected through optical follow-up of the 2nd ROSAT faint source catalogue with Dark Energy Survey year 3 data. The selection function is modelled by combining an empirically constructed X-ray selection function with an incompleteness model for the optical follow-up. We validate the joint selection function by testing the consistency of the constraints on the X-ray flux–mass and richness–mass scaling relation parameters derived from different sources of mass information: (1) cross-calibration using South Pole Telescope Sunyaev-Zel'dovich (SPT-SZ) clusters, (2) calibration using number counts in X-ray, in optical and in both X-ray and optical while marginalizing over cosmological parameters, and (3) other published analyses. We find that the constraints on the scaling relation from the number counts and SPT-SZ cross-calibration agree, indicating that our modelling of the selection function is adequate. Furthermore, we apply a largely cosmology independent method to validate selection functions via the computation of the probability of finding each cluster in the SPT-SZ sample in the MARD-Y3 sample and vice versa. This test reveals no clear evidence for MARD-Y3 contamination, SPT-SZ incompleteness or outlier fraction. Finally, we discuss the prospects of the techniques presented here to limit systematic selection effects in future cluster cosmological studies.

We improve the pNRQCD approach to annihilation processes of heavy quarkonium and make first pNRQCD predictions for exclusive electromagnetic production of heavy quarkonium. We consider strongly coupled quarkonia, i.e., quarkonia that are not Coulombic bound states. Possible strongly coupled quarkonia include excited charmonium and bottomonium states. For these, pNRQCD provides expressions for the decay and exclusive electromagnetic production NRQCD matrix elements that depend on the wavefunctions at the origin and few universal gluon field correlators. We compute electromagnetic decay widths and exclusive production cross sections, and inclusive decay widths into light hadrons for P -wave quarkonia at relative order v$^{2}$ and leading order, respectively. We also compute the decay widths of 2S and 3S bottomonium states into lepton pairs and their ratios with the inclusive widths into light hadrons at relative order v$^{2}$.

We present a general formalism to write the decay amplitude for multibody reactions with explicit separation of the rotational degrees of freedom, which are well controlled by the spin of the decay particle, and dynamic functions on the subchannel invariant masses, which require modeling. Using the three-particle kinematics we demonstrate the proposed factorization, named the Dalitz-plot decomposition. The Wigner rotations, which are subtle factors needed by the isobar modeling in the helicity framework, are simplified with the proposed decomposition. Consequently, we are able to provide them in an explicit form suitable for the general case of arbitrary spins. The only unknown model-dependent factors are the isobar line shapes that describe the subchannel dynamics. The advantages of the new decomposition are shown through three examples relevant for the recent discovery of the exotic charmonium candidate Z_c(4430 ), the pentaquarks P_c, and the intriguing Λ_c⁺→p K^-π⁺ decay.

We combine the NLTE spectral analysis of the detached O-type eclipsing binary OGLE-LMC-ECL-06782 with the analysis of the radial velocity curve and light curve to measure an independent distance to the Large Magellanic Cloud (LMC). In our spectral analysis we study composite spectra of the system at quadrature and use the information from radial velocity and light curve about stellar gravities, radii, and component flux ratio to derive effective temperature, reddening, extinction, and intrinsic surface brightness. We obtain a distance modulus to the LMC of m - M = 18.53 ± 0.04 mag. This value is 0.05 mag larger than the precision distance obtained recently from the analysis of a large sample of detached, long period late spectral type eclipsing binaries but agrees within the margin of the uncertainties. We also determine the surface brightnesses of the system components and find good agreement with the published surface brightness-color relationship. A comparison of the observed stellar parameters with the prediction of stellar evolution based on the MESA stellar evolution code shows reasonable agreement, but requires a reduction of the internal angular momentum transport to match the observed rotational velocities.

Origins of contemporary $B$-physics. Mesons with beauty and charm. Stable tetraquarks? Flavor and the problem of identity. Top matters. Electroweak symmetry breaking and the Higgs sector. Future instruments.

The simultaneous study of top-down and bottom-up approaches to modular flavor symmetry leads necessarily to the concept of eclectic flavor groups. These are non-trivial products of modular and traditional flavor symmetries that exhibit the phenomenon of local flavor enhancement in moduli space. We develop methods to determine the eclectic flavor groups that can be consistently associated with a given traditional flavor symmetry. Applying these methods to a large family of prominent traditional flavor symmetries, we try to identify potential candidates for realistic eclectic flavor groups and show that they are relatively rare. Model building with finite modular flavor symmetries thus appears to be much more restrictive than previously thought.

We show that for a wide range of stellar masses, from 0.3 to 20 M_⊙, and for evolutionary phases from the main sequence to the beginning of the red giant stage, the stellar flux-weighted gravity, g_F ≅ g/ ${T}_{\mathrm{eff}}^{4}$ , is tightly correlated with absolute bolometric magnitude ${M}_{\mathrm{bol}}$ . Such a correlation is predicted by stellar evolution theory. We confirm this relation observationally, using a sample of 445 stars with precise stellar parameters. It holds over 17 stellar magnitudes from ${M}_{\mathrm{bol}}$ = 9.0 to -8.0 mag with a scatter of 0.17 mag above ${M}_{\mathrm{bol}}$ = -3.0 and 0.29 mag below this value. We then test the relation with 2.2 million stars with 6.5 mag ≥ ${M}_{\mathrm{bol}}$ ≥ 0.5 mag, where "mass-produced" but robust $\mathrm{log}\,g$ , ${T}_{{\rm{e}}{\rm{f}}{\rm{f}}},$ and ${M}_{\mathrm{bol}}$ from LAMOST DR5 and Gaia DR2 are available. We find that the same relation holds with a scatter of ∼0.2 mag for single stars offering a simple spectroscopic distance estimate good to ∼10%.

We present a 7 minute long 4π-3D simulation of a shell merger event in a nonrotating 18.88 ${M}_{\odot }$ M ⊙ supernova progenitor before the onset of gravitational collapse. The key motivation is to capture the large-scale mixing and asymmetries in the wake of the shell merger before collapse using a self-consistent approach. The 4π geometry is crucial, as it allows us to follow the growth and evolution of convective modes on the largest possible scales. We find significant differences between the kinematic, thermodynamic, and chemical evolution of the 3D and 1D models. The 3D model shows vigorous convection leading to more efficient mixing of nuclear species. In the 3D case, the entire oxygen shell attains convective Mach numbers of ≈0.1, whereas in the 1D model, the convective velocities are much lower, and there is negligible overshooting across convective boundaries. In the 3D case, the convective eddies entrain nuclear species from the neon (and carbon) layers into the deeper part of the oxygen-burning shell, where they burn and power a violent convection phase with outflows. This is a prototypical model of a convective-reactive system. Due to the strong convection and resulting efficient mixing, the interface between the neon layer and the silicon-enriched oxygen layer disappears during the evolution, and silicon is mixed far out into the merged oxygen/neon shell. Neon entrained inward by convective downdrafts burns, resulting in lower neon mass in the 3D model compared to the 1D model at the time of collapse. In addition, the 3D model develops remarkable large-scale, large-amplitude asymmetries, which may have important implications for the impending gravitational collapse and subsequent explosion.

We consider scenarios with a heavy Z' gauge boson with flavour non-universal quark and lepton couplings with the goal to illustrate how the cancellation of gauge anomalies generated by the presence of an additional U(1)' gauge symmetry would imply correlations between FCNC processes within the quark sector, within the lepton sector and most interestingly between quark flavour and lepton flavour violating processes. To this end we present simple scenarios with only left-handed flavour-violating Z' couplings and those in which also right-handed flavour-violating couplings are present. The considered scenarios are characterized by a small number of free parameters but in contrast to gauge anomaly cancellation in the Standard Model, in which it takes place separately within each generation, in our scenarios anomaly cancellation involves simultaneously quarks and leptons of all three generations. Our models involve, beyond the ordinary quarks and leptons, three heavy right-handed neutrinos. The models with only left-handed FCNCs of Z' involve beyond g_Z^' and M_Z^' two real parameters characterizing the charges of all fermions under the U(1)' gauge symmetry and the CKM and PMNS ones in the quark and lepton sectors, respectively. The models with the right-handed FCNCs of Z' involve few additional parameters. Imposing constraints from well measured ΔF = 2 observables we identify a number of interesting correlations that involve e.g. ɛ'/ɛ, B_s,d→ μ⁺μ^-, B → K(K^*)ℓ⁺ℓ^-, K⁺→π⁺ν ν ¯,K_L→π⁰ν ν ¯ and purely lepton flavour violating decays like μ → eγ, μ → 3e, τ → 3μ and μ - e conversion among others. Also (g - 2)μ,e are considered. The impact of the experimental μ → eγ, μ → 3e and in particular μ - e conversion bounds on rare K and B decays is emphasized.

Light curves, explosion energies, and remnant masses are calculated for a grid of supernovae resulting from massive helium stars that have been evolved including mass loss. These presupernova stars should approximate the results of binary evolution for stars in interacting systems that lose their envelopes close to the time of helium core ignition. Initial helium star masses are in the range 2.5-40 M_⊙, which corresponds to main-sequence masses of about 13-90 M_⊙. Common SNe Ib and Ic result from stars whose final masses are approximately 2.5-5.6 M_⊙. For heavier stars, a large fraction of collapses lead to black holes, though there is an island of explodability for presupernova masses near 10 M_⊙. The median neutron star mass in binaries is 1.35-1.38 M_⊙, and the median black hole mass is between 9 and 11 M_⊙. Even though black holes less massive than 5 M_⊙ are rare, they are predicted down to the maximum neutron star mass. There is no empty "gap," only a less populated mass range. For standard assumptions regarding the explosions and nucleosynthesis, the models predict light curves that are fainter than the brighter common SNe Ib and Ic. Even with a very liberal but physically plausible increase in ⁵⁶Ni production, the highest-energy models are fainter than 10^42.6 erg s^-1 at peak, and very few approach that limit. The median peak luminosity ranges from 10^42.0 to 10^42.3 erg s^-1. Possible alternatives to the standard neutrino-powered and radioactive-illuminated models are explored. Magnetars are a promising alternative. Several other unusual varieties of SNe I at both high and low mass are explored.

Following updated and extended measurements of the full angular distribution of the decay Λb→Λ(→pπ−)μ+μ− by the LHCb collaborations, as well as a new measurement of the Λ→pπ− decay asymmetry parameter by the BESIII collaboration, we study the impact of these results on searches for non-standard effects in exclusive b→sμ+μ− decays. To this end, we constrain the Wilson coefficients 9 and 10 of the numerically leading dimension-six operators in the weak effective Hamiltonian, in addition to the relevant nuisance parameters. In stark contrast to previous analyses of this decay mode, the changes in the updated experimental results lead us to find very good compatibility with both the Standard Model and with the b→sμ+μ− anomalies observed in rare B-meson decays. We provide a detailed analysis of the impact of the partial angular distribution, the full angular distribution, and the Λb→Λμ+μ− branching fraction on the Wilson coefficients. In this process, we are also able to constrain the size of the production polarization of the Λb baryon at LHCb.

Aims: We investigate electron temperature (T_e) and gas-phase oxygen abundance (Z_Te) measurements for galaxies in the local Universe (z < 0.25). Our sample comprises spectra from a total of 264 emission-line systems, ranging from individual HII regions to whole galaxies, including 23 composite HII regions from star-forming main sequence galaxies in the MaNGA survey.
Methods: We utilise 130 of these systems with directly measurable T_e(OII) to calibrate a new metallicity-dependent T_e(OIII)-T_e(OII) relation that provides a better representation of our varied dataset than existing relations from the literature. We also provide an alternative T_e(OIII)-T_e(NII) calibration. This new T_e method is then used to obtain accurate Z_Te estimates and form the mass - metallicity relation (MZR) for a sample of 118 local galaxies.
Results: We find that all the T_e(OIII)-T_e(OII) relations considered here systematically under-estimate Z_Te for low-ionisation systems by up to 0.6 dex. We determine that this is due to such systems having an intrinsically higher O⁺ abundance than O⁺⁺ abundance, rendering Z_Te estimates based only on [OIII] lines inaccurate. We therefore provide an empirical correction based on strong emission lines to account for this bias when using our new T_e(OIII)-T_e(OIII) and T_e(OIII)-T_e(NII) relations. This allows for accurate metallicities (1σ = 0.08 dex) to be derived for any low-redshift system with an [OIII]λ4363 detection, regardless of its physical size or ionisation state. The MZR formed from our dataset is in very good agreement with those formed from direct measurements of metal recombination lines and blue supergiant absorption lines, in contrast to most other T_e-based and strong-line-based MZRs. Our new T_e method therefore provides an accurate and precise way of obtaining Z_Te for a large and diverse range of star-forming systems in the local Universe.

Cosmic voids are biased tracers of the large-scale structure of the universe. Separate universe simulations (SUS) enable accurate measurements of this biasing relation by implementing the peak-background split (PBS). In this work, we apply the SUS technique to measure the void bias parameters. We confirm that the PBS argument works well for underdense tracers. The response of the void size distribution depends on the void radius. For voids larger (smaller) than the size at the peak of the distribution, the void abundance responds negatively (positively) to a long wavelength mode. The linear bias from the SUS is in good agreement with the cross power spectrum measurement on large scales. Using the SUS, we have detected the quadratic void bias for the first time in simulations. We find that b₂ is negative when the magnitude of b₁ is small, and that it becomes positive and increases rapidly when $| {b}_{1}| $ increases. We compare the results from voids identified in the halo density field with those from the dark matter distribution, and find that the results are qualitatively similar, but the biases generally shift to the larger voids sizes.