Papers for Friday, Apr 29 2022

We present an analytic model of the stellar mass distribution of the Milky Way bar. The model is obtained by fitting a multi-component parametric density distribution to a made-to-measure N-body model of Portail et al., constructed to match a variety of density and kinematics observational data. The analytic model reproduces in detail the 3D density distribution of the N-body bar including the X-shape. The model and the gravitational potential it generates are available as part of the software package AGAMA for galactic dynamics, and can be readily used for orbit integrations, hydrodynamical simulations or other applications.

Ultra-short period planets offer a window into the poorly understood interior composition of exoplanets through material evaporated from their rocky interiors. Among these objects are a class of disintegrating planets, observed when their dusty tails transit in front of their host stars. These dusty tails are thought to originate from dust condensation in thermally-driven winds from the sublimating surfaces of these planets. Existing models of these winds have been unable to explain their highly variable nature or explain how dust forms in the wind - through which these systems were originally detected. Here we present new radiation-hydrodynamic simulations of the winds from these planets, including a model for formation and destruction of dust. We find that dust forms readily in the winds, a consequence of large dust grains obtaining lower temperatures than the planet's surface. Furthermore, we find that the coupling of the planet's surface temperature to the outflow properties via the dust opacity can drive time-variable flows when dust condensation is sufficiently fast. In agreement with previous work, our models suggest that these dusty tails are a signature of catastrophically evaporating planets that are close to the end of their lives. Finally, we discuss the implications of our results for the dust's composition, but more detailed hydrodynamic models that self-consistently compute the composition of the dust and gas are warranted to link the dust properties to the planet's interior composition.

This paper describes a new technique for determining the optimal period of a pulsar and consequently its light curve. The implemented technique makes use of the Principal Component Analysis (PCA) applied to the so-called waterfall diagram, which is a bidimensional representation of the pulsar acquired data. In this context we have developed the python package pywpf to easily retrieve the period with the presented method. We applied this technique to sets of data of the brightest pulsars in visible light that we obtained with the fast photon counter Iqueye. Our results are compared with those obtained by different and more classical analyses (e.g., epoch folding), showing that the periods so determined agree within the errors, and that the errors associated to the waterfall-PCA folding technique are slightly smaller than those obtained by the $\chi^2$ epoch folding technique. We also simulated extremely noisy situations, showing that by means of a new merit function associated to the waterfall-PCA folding it is possible to get more confidence on the determined period with respect to the $\chi^2$ epoch folding technique.

In the framework of studies of the CMB polarization and its Galactic foregrounds, the angular power spectra of thermal dust polarization maps have revealed an intriguing E/B asymmetry and a positive TE correlation. In interpretation studies of these observations, magnetized ISM dust clouds have been treated as filamentary structures only; however, sheet-like shapes are also supported by observational and theoretical evidence. In this work, we study the influence of cloud shape and its connection to the local magnetic field on angular power spectra of thermal dust polarization maps. We simulate realistic filament-like and sheet-like interstellar clouds, and generate synthetic maps of their thermal dust polarized emission using the software $Asterion$. We compute their polarization power spectra in multipole range $\ell \in [100,500]$ and quantify the E/B power asymmetry through the $R_{EB}$ ratio, and the correlation coefficient $r^{TE}$ between T and E modes. We quantify the dependence of $R_{EB}$ and $r^{TE}$ values on the offset angle (between longest cloud axis and magnetic field) and inclination angle (between line-of-sight and magnetic field) for both cloud shapes embedded either in a regular or a turbulent magnetic field. We find that both cloud shapes cover the same regions of the ($R_{EB}$, $r^{TE}$) parameter space. The dependence on inclination and offset angles are similar for both shapes although sheet-like structures generally show larger scatter. In addition to the known dependence on the offset angle, we find a strong dependence of $R_{EB}$ and $r^{TE}$ on the inclination angle. The fact that filament-like and sheet-like structures may lead to polarization power spectra with similar ($R_{EB}$, $r^{TE}$) values complicates their interpretation. In future analyses, this degeneracy should be accounted for as well as the connection to the magnetic field geometry.

We present a percent-level accurate model of the line-of-sight velocity distribution of galaxies around dark matter halos as a function of projected radius and halo mass. The model is developed and tested using synthetic galaxy catalogs generated with the UniverseMachine run on the Multi-Dark Planck 2 N-body simulations. The model decomposes the galaxies around a cluster into three kinematically distinct classes: orbiting, infalling, and interloping galaxies. We demonstrate that: 1) we can statistically distinguish between these three types of galaxies using only projected line-of-sight velocity information; 2) the halo edge radius inferred from the line-of-sight velocity dispersion is an excellent proxy for the three-dimensional halo edge radius; 3) we can accurately recover the full velocity dispersion profile for each of the three populations of galaxies. Importantly, the velocity dispersion profiles of the orbiting and infalling galaxies contain five independent parameters -- three distinct radial scales and two velocity dispersion amplitudes -- each of which is correlated with mass. Thus, the velocity dispersion profile of galaxy clusters has inherent redundancies that allow us to perform nontrivial systematics check from a single data set. We discuss several potential applications of our new model for detecting the edge radius and constraining cosmology and astrophysics using upcoming spectroscopic surveys.

Sub-arcsecond imaging of the X-ray emission in the type 2 AGN Mrk 78 with Chandra shows complex structure with spectral variations on scales from $\sim$200 pc to $\sim$ 2 kpc. Overall the X-ray emission is aligned E-W with the radio (3.6 cm) and narrow emission line region as mapped in [OIII], with a marked E-W asymmetry. The Eastern X-ray emission is mostly in a compact knot coincident with the location where the radio source is deflected, while the Western X-ray emission forms a loop or shell $\sim$2 kpc from the nucleus with radius $\sim$0.7 kpc. There is suggestive evidence of shocks in both the Eastern knot and the Western arc. Both these positions coincide with large changes in the velocities of the [OIII] outflow. We discuss possible reasons why the X-ray shocks on the Western side occur $\sim1$ kpc farther out than on the Eastern side. We estimate that the thermal energy injected by the shocks into the interstellar medium corresponds to $0.05-0.6$% of the AGN bolometric luminosity.

We report the results of X-ray (CXO) and radio (ATCA) observations of the pulsar wind nebula (PWN) powered by the young pulsar PSR J1016--5857, which we dub "the Goose" PWN. In both bands the images reveal a tail-like PWN morphology which can be attributed to pulsar's motion. By comparing archival and new CXO observations, we measure the pulsar's proper motion $\mu=28.8\pm7.3$ mas/yr, yielding a projected pulsar velocity $v \approx 440\pm110$ km/s (at d=3.2 kpc); its direction is consistent with the PWN shape. Radio emission from the PWN is polarized, with the magnetic field oriented along the pulsar tail. The radio tail connects to a larger radio structure (not seen in X-rays) which we interpret as a relic PWN (also known as a plerion). The spectral analysis of the CXO data shows that the PWN spectrum softens from $\Gamma=1.7$ to $\Gamma\approx2.3-2.5$ with increasing distance from the pulsar. The softening can be attributed to rapid synchrotron burn-off, which would explain the lack of X-ray emission from the older relic PWN. In addition to non-thermal PWN emission, we detected thermal emission from a hot plasma which we attribute to the host SNR. The radio PWN morphology and the proper motion of the pulsar suggest that the reverse shock passed through the pulsar's vicinity and pushed the PWN to one side.

Quiescent filaments appear as absorption features on the solar disk when observed in chromospheric lines and at continuum wavelengths in the millimeter (mm) range. Active region (AR) filaments are their small-scale, low-altitude analogues, but they could not be resolved in previous mm observations. This spectral diagnostic can provide insight into the details of the formation and physical properties of their fine threads, which are still not fully understood. Here, we shed light on the thermal structure of an AR filament using high-resolution brightness temperature ($T_{\rm b}$) maps taken with ALMA Band 6 complemented by simultaneous IRIS near-UV spectra, Hinode/SOT photospheric magnetograms, and SDO/AIA extreme-UV images. Some of the dark threads visible in the AIA 304 {\AA} passband and in the core of Mg II resonance lines have dark ($T_{\rm b}<5000$K) counterparts in the 1.25 mm maps, but their visibility significantly varies across the filament spine and in time. These opacity changes are possibly related to variations in temperature and electron density in filament fine structures. The coolest $T_{\rm b}$ values ($<$5000 K) coincide with regions of low integrated intensity in the Mg II h and k lines. ALMA Band 3 maps taken after the Band 6 ones do not clearly show the filament structure, contrary to the expectation that the contrast should increase at longer wavelengths based on previous observations of quiescent filaments. The ALMA maps are not consistent with isothermal conditions, but the temporal evolution of the filament may partly account for this.

Based on the occurrence rates implied by the discoveries of 1I/`Oumuamua and 2I/Borisov, the forthcoming Rubin Observatory Legacy Survey of Space and Time (LSST) should detect $\ge1$ interstellar comets every year (Hoover et al. 2021). We advocate for future measurements of the production rates of H$_2$O, CO$_2$ and CO in these comets to estimate their carbon to oxygen ratios, which traces formation locations within their original protoplanetary disks. We review similar measurements for Solar System comets, which indicate formation interior to the CO snowline. By quantifying the relative processing in the interstellar medium and Solar System, we estimate that production rates will not be representative of primordial compositions for the majority of interstellar comets. Preferential desorption of CO and CO$_2$ relative to H$_2$O in the interstellar medium implies that measured C/O ratios represent lower limits on the primordial ratios. Specifically, production rate ratios of ${\rm Q}({\rm CO})/{\rm Q}({\rm H_2O})<.2$ and ${\rm Q}({\rm CO})/{\rm Q}({\rm H_2O})>1$ likely indicate formation interior and exterior to the CO snowline, respectively. The high C/O ratio of 2I/Borisov implies that it formed exterior to the CO snowline. We provide an overview of the currently operational facilities capable of obtaining these measurements that will constrain the fraction of ejected comets that formed exterior to the CO snowline. This fraction will provide key insights into the efficiency of and mechanisms for cometary ejection in exoplanetary systems.

Gas-phase and solid-state chemistry in low-temperature interstellar clouds and cores leads to a D/H enhancement in interstellar ices, which is eventually inherited by comets, meteorites, and even planetary satellites. Hence, the D/ H ratio has been widely used as a tracer for the origins of extraterrestrial chemistry. However, the D/H ratio can also be influenced by cosmic rays, which are ubiquitous and can penetrate even dense interstellar molecular cores. The effects of such high-energy radiation on deuterium fractionation have not been studied in a quantitative manner. In this study, we present rate constants for radiation-induced D-to-H exchange for fully deuterated small (1-2 C) hydrocarbons embedded in H2O ice at 20 K and H-to-D exchange for the protiated forms of these molecules in D2O ice at 20 K. We observed larger rate constants for H-to-D exchange in the D2O ice versus D-to-H exchange in H2O ice, which we have attributed to the greater bond strength of C-D versus C-H. We find that the H-to-D exchange rate constants are smaller for protiated methane than ethane, in agreement with bond energies from the literature. We are unable to obtain rate constants for the unsaturated and reactive hydrocarbons ethylene and acetylene. Interpretation of the rate constants suggest that D/H exchange products are formed in abundance alongside radiolysis products. We discuss how our quantitative and qualitative data can be used to interpret the D/ H ratios of aliphatic compounds observed throughout space.

Most cosmic shear analyses to date have relied on summary statistics (e.g. $\xi_+$ and $\xi_-$). These types of analyses are necessarily sub-optimal, as the use of summary statistics is lossy. In this paper, we forward-model the convergence field of the Universe as a lognormal random field conditioned on the observed shear data. This new map-based inference framework enables us to recover the joint posterior of the cosmological parameters and the convergence field of the Universe. Our analysis properly accounts for the covariance in the mass maps across tomographic bins, which significantly improves the fidelity of the maps relative to single-bin reconstructions. We verify that applying our inference pipeline to Gaussian random fields recovers posteriors that are in excellent agreement with their analytical counterparts. At the resolution of our maps -- and to the extent that the convergence field can be described by the lognormal model -- our map posteriors allow us to reconstruct \it all \rm summary statistics (including non-Gaussian statistics). We forecast that a map-based inference analysis of LSST-Y10 data can improve cosmological constraints in the $\sigma_8$--$\Omega_{\rm m}$ plane by $\approx 30\%$ relative to the currently standard cosmic shear analysis. This improvement happens almost entirely along the $S_8=\sigma_8\Omega_{\rm m}^{1/2}$ directions, meaning map-based inference fails to significantly improve constraints on $S_8$.

We present a method to determine the static aberrations in a nearly diffraction-limited spectrograph introduced, for example, by alignment or manufacturing errors. We consider an instrument with two stages separated by a slit or image slicer located in the intermediate focal plane. In such a spectrograph, it is not trivial to distinguish aberrations in the first stage, before the slit, from those in the second, after the slit. However, our method achieves this. Measuring these aberrations separately opens the possibility of reducing them, by realignment or other means, and thereby improving the optical performance of the instrument. The method is based on fitting models to multiple images of a point source, with controlled displacements of the source perpendicular to the slit and controlled defocuses of the second stage or the detector. Fitting models to these images allows the determination of the aberrations in both stages. Our key discovery is that the displaced and defocused images provide additional information which allows us to break the ambiguity between the two stages. We present simulations that validate the performance of the method.

The bimodal absorption system imaging campaign (BASIC) aims to characterize the galaxy environments of a sample of 36 HI-selected partial Lyman limit systems (pLLSs) and Lyman limit systems (LLSs) in 23 QSO fields at $z \lesssim 1$. These pLLSs/LLSs provide a unique sample of absorbers with unbiased and well-constrained metallicities, allowing us to explore the origins of metal-rich and low-metallicity circumgalactic medium (CGM) at $z<1$. Here we present Keck/KCWI and VLT/MUSE observations of 11 of these QSO fields (19 pLLSs) that we combine with HST/ACS imaging to identify and characterize the absorber-associated galaxies. We find 23 unique absorber-associated galaxies, with an average of one associated galaxy per absorber. For seven absorbers, all with $<10\%$ solar metallicities, we find no associated galaxies with $\log M_\star \gtrsim 9.0$ within $\rho/R_{vir}$ and $|\Delta v|/v_{esc} \le$ 1.5 with respect to the absorber. We do not find any strong correlations between the metallicities or HI column densities of the gas and most of the galaxy properties, except for the stellar mass of the galaxies: the low-metallicity ([X/H] $\le -1.4$) systems have a probability of $0.39^{+0.16}_{-0.15}$ for having a host galaxy with $\log M_\star \ge 9.0$ within $\rho/R_{vir} \le 1.5$, while the higher metallicity absorbers have a probability of $0.78^{+0.10}_{-0.13}$. This implies metal-enriched pLLSs/LLSs at $z<1$ are typically associated with the CGM of galaxies with $\log M_\star > 9.0$, whereas low-metallicity pLLSs/LLSs are found in more diverse locations, with one population arising in the CGM of galaxies and another more broadly distributed in overdense regions of the universe. Using absorbers not associated with galaxies, we estimate the unweighted geometric mean metallicity of the intergalactic medium to be [X/H] $\lesssim -2.1$ at $z<1$, which is lower than previously estimated.

While it is generally believed that supermassive black holes (SMBH) lie in most galaxies with bulges, few SMBHs have been confirmed in bulgeless galaxies. Identifying such a population could provide important insights to the BH seed population and secular BH growth. To this end, we obtained near-infrared spectroscopic observations of a sample of low-redshift bulgeless galaxies with mid-infrared colors suggestive of AGN. We find additional evidence of AGN activity (such as coronal lines and broad permitted lines) in 69$\%$ (9/13) of the sample, demonstrating that mid-infrared selection is a powerful tool to detect AGN. More than half of the galaxies with confirmed AGN activity show fast outflows in [O III] in the optical and/or [Si VI] in the NIR, with the latter generally having much faster velocities that are also correlated to their spatial extent. We are also able to obtain virial BH masses for some targets and find they fall within the scatter of other late-type galaxies in the $M_{\rm{BH}}$-$M_{\rm{stellar}}$ relation. The fact that they lack a significant bulge component indicates that secular processes, likely independent of major mergers, grew these BHs to supermassive sizes. Finally, we analyze the rotational gas kinematics and find two notable exceptions: two AGN hosts with outflows that appear to be rotating faster than expected. There is an indication that these two galaxies have stellar masses significantly lower than expected from their dark matter halo masses. This, combined with the observed AGN activity and strong gas outflows may be evidence of the effects of AGN feedback.

We present the detection of a broad 8 $\mu$m feature in newly formed dust around the carbon-rich Wolf-Rayet (WC) binary WR 125 from N-band low-resolution (NL; R$\sim$250) spectroscopy between 7.3-13.6 $\mu$m and N-band (11.7 $\mu$m) and Q-band (18.8 $\mu$m) imaging with Subaru/COMICS in 2019 October. WR 125 is a colliding wind binary (${\rm WC7+O9}$) that exhibited renewed dust formation starting in 2018, $\sim$28 years after its first dust formation episode had been observed. We also compare our infrared photometry with historical observations and revise the dust-formation period of WR 125 to 28.1 years. Archival infrared spectra of five dusty WC stars, WR 48a, WR 98a, WR 104, WR 112 and WR 118, obtained with ISO/SWS are reanalyzed and compared with the WR 125 spectrum to search for a similar feature. We analyze the dusty WC spectra using two different extinction curves to investigate the impact of interstellar extinction correction on the presence and/or properties of the 8 $\mu$m feature. All of the dusty WC spectra dereddened with the two different extinction curves show a broad feature around 8 $\mu$m (FWHM$\sim$1-2 $\mu$m). We suggest that these 8 $\mu$m features seen in the dusty WC spectra are related to the Class C unidentified infrared (UIR) features.

Association of GW170817/GRB170817A/AT2017gfo provides the first direct evidence for neutron star mergers as significant sources of $r$-process nucleosynthesis. A gamma-ray transient (GRT) would be powered by the radioactive decay of the freshly-synthesized $r$-process elements. By analyzing the composition and gamma-ray opacity of the kilonova ejecta in details, we calculate the lightcurve and spectrum of the GRT for a spherically symmetric merger ejecta with mass $M_{\rm ej}=0.001 \sim 0.05M_{\odot}$ and expansion velocity $v_{\rm ej}= 0.1\sim 0.4c$. It is found that the peak of the GRT lightcurve depends on $M_{\rm ej}$ and $v_{\rm ej}$ as $t_{\rm pk} \approx 0.9~{\rm days} ~ (M_{\rm ej}/0.01M_{\odot})^{1/2}(v_{\rm ej}/0.2c)^{-1}$ and $L_{\rm pk} \approx 7.0\times10^{40} ~{\rm erg~s} ^{-1} (M_{\rm ej}/0.01M_{\odot})^{1/2}(v_{\rm ej}/0.2c)$. Most radiating photons are in the $100-3000$ keV band and the spectrum peaks at round 800 keV for different nuclear physics inputs. The line features are blurred out by the Doppler broadening effect and the uncertainties of nuclear physics data. Adopting the ejecta parameters reported in literature, we examine the detection probability of the possible GRT associated with AT2017gfo. We show that the GRT cannot be convincingly detected with the proposed missions in the MeV band, such as ETCC and AMEGO. The low gamma-ray flux, together with the extremely low event rate at local universe, makes a great challenge for discovery of the GRTs.

The inverse Compton process by which soft photons are up-scattered by hot electrons in a corona plays a fundamental role in shaping the X-ray spectra of black-hole (BH) low-mass X-ray binaries (LMXBs), particularly in the hard and hard-intermediate states. In these states, the power-density spectra of these sources typically show Type-C low-frequency quasi-periodic oscillations (QPOs). Although several models have been proposed to explain the dynamical origin of their frequency, only a few of those models predict the spectral-timing radiative properties of the QPOs. Here we study the physical and geometrical properties of the corona of the BH-LMXB GRS 1915+105 based on a large sample of observations available in the RXTE archive. We use a recently-developed spectral-timing Comptonisation model to fit simultaneously the energy-dependent fractional rms amplitude and phase-lag spectra of the Type-C QPO in 398 observations. For this, we include spectral information gathered from fitting a Comptonisation model to the corresponding time-averaged spectra. We analyse the dependence of the physical and geometrical properties of the corona upon the QPO frequency and spectral state of the source, the latter characterised by the hardness ratio. We find consistent trends in the evolution of the corona size, temperature, and feedback (the fraction of the corona photons that impinge back onto the disc) that persist for roughly 15~years. By correlating our observations with simultaneous radio-monitoring of the source at 15 GHz, we propose a scenario in which the disc-corona interactions connect with the launching mechanism of the radio jet in this source.

We study the evolution of magnetic fields in cosmic string wakes in a plasma with a low resistivity. The initial magnetic field in the wake is modelled on the magnetic fields that are generated by the motion of particles around cosmic strings. The plasma is characterized by a high beta value. We find multiple shock like structures developing in the wake of the string. We study the detailed structure of the shocks formed and the evolution of the magnetic field in the shock using a 2-D magnetohydrodynamic simulation. As expected, the development of the magnetic field does not depend on the $\beta$ value. Our results show that instead of a singe uniform shock forming behind the cosmic string we have multiple shocks forming at short time intervals behind the string. The presence of multiple shocks will definitely affect the observational signatures of cosmic string wakes as these signatures depend upon the temperature fluctuations generated by the shock. We also find that as the shock moves away, the residual magnetic field left behind reconnects and dissipates rapidly. The magnetic field around the string is thus very localized. We find that magnetic field reconnections take place in cosmic string wakes. This leads to the decrease of the magnetic field in the post shock region.

Giant planets have been discovered at large separations from the central star. Moreover, a striking number of young circumstellar disks have gas and/or dust gaps at large orbital separations, potentially driven by embedded planetary objects. To form massive planets at large orbital separations through core accretion within disk lifetime, however, an early solid body to seed pebble and gas accretion is desirable. Young protoplanetary disks are likely self-gravitating, and these gravitoturbulent disks may efficiently concentrate solid material at the midplane driven by spiral waves. We run 3D local hydrodynamical simulations of gravitoturbulent disks with Lagrangian dust particles to determine whether particle and gas self-gravity can lead to the formation of dense solid bodies, seeding later planet formation. When self-gravity between dust particles is included, solids of size $\mathrm{St} = 0.1$ to $1$ concentrate within the gravitoturbulent spiral features and collapse under their own self-gravity into dense clumps up to several $M_{\oplus}$ in mass at wide orbits. Simulations with dust that drift most efficiently, $\mathrm{St}=1$, form the most massive clouds of particles, while simulations with smaller dust particles, $\mathrm{St}=0.1$, have clumps with masses an order of magnitude lower. When the effect of dust backreaction onto the gas is included, dust clumps become smaller by a factor of a few but more numerous. The existence of large solid bodies at an early stage of the disk can accelerate the planet formation process, particularly at wide orbital separations, and potentially explain planets distant from the central stars and young protoplanetary disks with substructures.

We present a comprehensive spectral and temporal study of the black hole X-ray transient MAXI J1820+070 during its outbursts in 2018 using Swift/XRT, NICER, NuSTAR and AstroSat observations. The Swift/XRT and NICER spectral study shows a plateau in the light curve with spectral softening (hardness changes from $\sim$ $2.5$ to $2$) followed by a gradual decline without spectral softening during the first outburst. Also, spectral modelling suggests that the first outburst is in the low/hard state throughout with a truncated disk whereas the thermal disk emission dominates during the second outburst. During the entire outburst, strong reflection signature (reflection fraction varies between $\sim$ $0.38 - 3.8$) is observed in the simultaneous wideband (NICER-NuSTAR, XRT-NuSTAR, AstroSat) data due to the presence of a dynamically evolving corona. The NICER timing analysis shows Quasi-periodic Oscillation (QPO) signatures and the characteristic frequency increases (decreases) in the plateau (decline) phase with time during the first outburst. We understand that the reduction of the electron cooling timescale in the corona due to spectral softening and the resonance oscillation with the local dynamical timescale may explain the above behavior of the source during the outburst. Also, we propose a possible scenario of outburst triggering and the associated accretion geometry of the source.

The first paper of this series established a linear stochastic wave equation for solar-like p-modes, correctly taking the effect of turbulence thereon into account. In this second paper, we aim at deriving simultaneous expressions for the excitation rate, damping rate, and modal surface effect associated with any given p-mode, as an explicit function of the statistical properties of the turbulent velocity field. We reduce the stochastic wave equation to complex amplitude equations for the normal oscillating modes of the system. We then derive the equivalent Fokker-Planck equation for the real amplitudes and phases of all the oscillating modes of the system simultaneously. The effect of the finite-memory time of the turbulent fluctuations (comparable to the period of the modes) on the modes themselves is consistently and rigorously accounted for, by means of the simplified amplitude equation formalism. This formalism accounts for mutual linear mode coupling in full, and we then turn to the special single-mode case. This allows us to derive evolution equations for the mean energy and mean phase of each mode, from which the excitation rate, the damping rate, and the modal surface effect naturally arise. We show that the expression for the excitation rate of the modes is identical to previous results obtained through a different modelling approach, thus supporting the validity of the formalism presented here. We also recover the fact that the damping rate and modal surface effect correspond to the real and imaginary part of the same single complex quantity. We explicitly separate the different physical contributions to these observables, in particular the turbulent pressure contribution and the joint effect of the pressure-rate-of-strain correlation and the turbulent dissipation. We show that the former dominates for high-frequency modes and the latter for low-frequency modes.

Although active galactic nuclei (AGN) feedback is required in simulations of galaxies to regulate star formation, further downstream effects on the dark matter distribution of the halo and stellar kinematics of the central galaxy can be expected. We combine simulations of galaxies with and without AGN physics from the Numerical Investigation of a Hundred Astrophysical Objects (NIHAO) to investigate the effect of AGN on the dark matter profile and central stellar rotation of the host galaxies. Specifically, we study how the concentration-halo mass ($c-M$) relation and the stellar spin parameter ($\lambda_R$) are affected by AGN feedback. We find that AGN physics is crucial to reduce the central density of simulated massive ($\gtrsim 10^{12}$ M$_\odot$) galaxies and bring their concentration to agreement with results from the Spitzer Photometry & Accurate Rotation Curves (SPARC) sample. Similarly, AGN feedback has a key role in reproducing the dichotomy between slow and fast rotators as observed by the ATLAS$^{3\text{D}}$ survey. Without star formation suppression due to AGN feedback, the number of fast rotators strongly exceeds the observational constraints. Our study shows that there are several collateral effects that support the importance of AGN feedback in galaxy formation, and these effects can be used to constrain its implementation in numerical simulations.

The near-absence of compact massive quiescent galaxies in the local Universe implies a size evolution since $z\sim2.5$. It is often theorised that such `red nuggets' have evolved into today's elliptical (E) galaxies via an E-to-E transformation. We examine an alternative scenario in which a red nugget develops a rotational disc through mergers and accretion, say, at $1\lesssim z\lesssim2$, thereby cloaking the nugget as the extant bulge/spheroid component of a larger, now old, galaxy. We have performed detailed, physically-motivated, multi-component decompositions of a volume-limited sample of 103 massive ($M_*/\rm M_{\odot} \gtrsim 1\times 10^{11}$) galaxies within 110\,Mpc. Among our 28 galaxies with existing elliptical classifications, we found that 18 have large-scale discs, and two have intermediate-scale discs, and are reclassified here as lenticulars (S0) and elliculars (ES). The local spheroid stellar mass function, size-mass diagram and bulge-to-total ($B/T$) flux ratio are presented. We report lower-limits for the volume number density of compact massive spheroids, $n_\mathrm{c,Sph}\sim (0.17$-$1.2) \times 10^{-4}\,\rm Mpc^{-3}$, based on different definitions of `red nuggets' in the literature. Similar number densities of local compact massive bulges were reported by de la Rosa et al. using automated two-component decompositions and their existence is now abundantly clear with our multi-component decompositions. We find disc-cloaking to be a salient alternative for galaxy evolution. In particular, instead of an E-to-E process, disc growth is the dominant evolutionary pathway for at least low-mass ($1\times10^{10}<M_*/\rm M_{\odot} \lessapprox 4 \times 10^{10}$) red nuggets, while our current lower-limits are within an alluring factor of a few of the peak abundance of high-mass red nuggets at $1\lesssim z\lesssim2$.

In a previous paper we studied the effect of latitudinal rotation on solar equatorial Rossby modes in the beta-plane approximation. Since then, a rich spectrum of inertial modes has been observed on the Sun, which is not limited to the equatorial Rossby modes and includes high-latitude modes. Here we extend the computation of toroidal modes in 2D to spherical geometry, using realistic solar differential rotation and including viscous damping. The aim is to compare the computed mode spectra with the observations and to study mode stability. At fixed radius, we solve the eigenvalue problem numerically using a spherical harmonics decomposition of the velocity stream function. Due to the presence of viscous critical layers, the spectrum consists of four different families: Rossby modes, high-latitude modes, critical-latitude modes, and strongly damped modes. For each longitudinal wavenumber m<4, up to three Rossby-like modes are present on the sphere, in contrast to the equatorial beta plane where only the equatorial Rossby mode is present. The least damped modes in the model have eigenfrequencies and eigenfunctions that resemble the observed modes; the comparison improves when the radius is taken in the lower half of the convection zone. For radii above 0.75R and Ekman numbers E<10^{-4}, at least one mode is unstable. For either m=1 or m=2, up to two Rossby modes are unstable when the radial dependence of the Ekman number follows a quenched diffusivity model (E=2. 10^{-5} at the base of the convection zone). For m=3, up to two Rossby modes can be unstable, including the equatorial Rossby mode. Although the 2D model discussed here is highly simplified, the spectrum of toroidal modes appears to include many of the observed solar inertial modes. The self-excited modes in the model have frequencies close to those of the observed modes with the largest amplitudes.

The evolution of the gravitational potentials on large scales due to the accelerated expansion of the Universe is an important and independent probe of dark energy, known as the integrated Sachs-Wolfe (ISW) effect. We measure this ISW effect through cross-correlating the cosmic microwave background maps from the \textit{Planck} satellite with a radio continuum galaxy distribution map from the recent Rapid ASKAP Continuum Survey (RACS). We detect a positive cross-correlation at $\sim 2.8\,\sigma$ relative to the null hypothesis of no correlation. We parameterise the strength of the ISW effect through an amplitude parameter and find the constraints to be $A_{\mathrm{ISW}} = 0.94^{+0.42}_{-0.41}$, which is consistent with the prediction of an accelerating universe within the current concordance cosmological model, $\Lambda$CDM. The credible interval on this parameter is independent of the different bias models and redshift distributions that were considered when marginalising over the nuisance parameters. We also detect a power excess in the galaxy auto-correlation angular power spectrum on large scales ($\ell \leq 40$), and investigate possible systematic causes.

We aim to constrain the dust mass and grain sizes in the interaction regions between the stellar winds and the ISM around asymptotic giant branch stars. By describing the dust in these regions, we aim to shed light on the role of low mass evolved stars in the origin of dust in galaxies. We use images in the far-infrared at 70 micron and 160 micron to derive dust temperatures and dust masses in the wind-ISM interaction regions around a sample of carbon-rich and oxygen-rich asymptotic giant branch (AGB) stars. The dust temperature and mass are determined in two ways. First directly from the data using the ratio of the measured fluxes and assuming opacities for dust with a constant grain size of 0.1 micron. We then perform 3D dust-radiative transfer models spatially constrained by the observations to consistently calculate the temperature and mass. For the radiative transfer models each model contains one constant grain size, which is varied between 0.01 micron to 5.0 micron. We find that the observed dust mass in the wind-ISM interaction regions is consistent with mass accumulated from the stellar winds. For the carbon-rich sources adding the spatial constraints in the radiative transfer models results in preferentially larger grain sizes (approx. 2 micron). For the oxygen-rich sources the spatial constraints result in too high temperatures in the models, making it impossible to fit the observed far-infrared ratio irrespective of the grain size used, indicating a more complex interplay of grain properties and the stellar radiation field. The results have implications for how likely it is for the grains to survive the transition into the ISM, and the properties of dust particles that later act as seeds for grain growth in the ISM. However, the results for the oxygen-rich sources show that the derivation of dust properties is not straight forward, requiring more complex modelling

Direct-imaging spectra hold rich information about a planet's atmosphere and surface, and several space-based missions aiming at such observations will become a reality in the near future. Previous spectral retrieval works have resulted in key atmospheric constraints under the assumption of a gray surface, but the effect of wavelength-dependent surface albedo on retrieval has not been shown. We explore the influence of the coupling effect of cloud and wavelength-dependent surface albedo on retrieval performance via modeling suites of Earth-like atmospheres with varying cloud and surface albedo parameterizations. Under the assumption of known cloud scattering properties, the surface spectral albedos can be reasonably recovered when the surface cover represents that of Earth-like vegetation or ocean, which may aid in characterizing the planet's habitability. When the cloud scattering properties cannot be assumed, we show that the degeneracy between the cloud properties and wavelength-dependent surface albedo leads to biased results of atmospheric and cloud properties. The multi-epoch visible band observations offer limited improvement in disentangling this degeneracy. However, the constraints on atmospheric properties from the combination of UV band (R $\sim 6$) $+$ visible band (R $\sim 140$) are consistent with input values to within 1 $\sigma$. If short bandpass data is not available, an alternative solution to reduce the retrieval uncertainties would be to have the prior constraints on planetary cloud fraction with less than 20% uncertainty.

In this work, we present a modelling of the galactic sub-clumps based on statistical estimations of the full Milky Way satellite population. We introduce 10 substructure modellings (SM$_{i}$, i $\in$ {1, . . . , 10}) with the following varying parameters: a) subhalos inner profile, b) spatial distribution of subhalos, c) mass distribution of subhalos, d) total number of subhalos and e) concentration parameter. The sensitivity curves of CTA for sources in each model are calculated for the $\tau^{+}\tau^{-}$ and $b\bar{b}$ annihilation channels. With both detection of a signal (5$\sigma$) with the CTA and no signal observation, no model was effective in accessing the thermal values of <$\sigma$ v>. We analyse the systematic effects introduced by the substructures models.

Long-term periodicity in the rate of flares is observed for two repeating sources of fast radio bursts (FRBs). In this paper We present a hydrodynamical modeling of a massive binary consisting of a magnetar and an early-type star. We model the interaction of the pulsar wind from the magnetar with an intense stellar wind. It is shown that only during a fraction of the orbital period radio emission can escape the system. This explains the duty cycle of the two repeating FRB sources with periodic activity. The width of the transparency window depends on the eccentricity, stellar wind properties, and the viewing angle. To describe properties of the known sources it is necessary to assume large eccentricities $\gtrsim 0.5$. We apply the maser cyclotron mechanism of the radio emission generation to model spectral properties of the sources. The produced spectrum is not wide: $\Delta \nu/\nu \sim 0.3$ and the typical frequency depends on the radius of the shock where the emission is generated. The shock radius changes along the orbit. This, together with changing parameters of the medium, allows us to explain the frequency drift during the phase of visibility. Frequency dependence of the degree of polarization at few GHz can be a consequence of a small scale turbulence in the shocked stellar wind. It is much more difficult to explain huge ($\sim 10^5$ [rad/m$^2$]) and variable value of the rotation measure observed for FRB 121102. We suggest that this can be explained if the supernova explosion which produced the magnetar happened near a dense interstellar cloud with $n \sim100$ cm$^{-3}$.

The mass, spin, and merger rate distribution of the binary black holes (BBHs) across cosmic redshifts provide a unique way to shed light on their formation channel. Along with the redshift dependence of the BBH merger rate, the mass distribution of BBHs can also exhibit redshift dependence due to different formation channels and due to its dependence on the metallicity of the parent stars. In this work, we explore the redshift dependence of the BBH mass distribution jointly with the merger rate evolution from the third gravitational wave (GW) catalog GWTC-3 of the LIGO-Virgo-KAGRA collaboration. This analysis sheds light on multiple new aspects of the BBH formation channel and mass distribution. We obtain interesting constraints on the minimum delay time between the formation of stars and mergers of BBHs $t^{\rm min}_d = 1.95^{+0.97}_{-0.93}$ Gyrs, along with a hint towards a steeper power-law form of the delay time distribution ($(t_d)^{d}$) with a index $d < -1.55$ at 68$\%$ C.L. The mass distribution of the BBHs agrees with a power-law form with a Gaussian peak at $\mu_g=40.26^{+1.04}_{-2.32} $ $\rm M_\odot$ which agrees with the theoretical prediction of the lower edge of the PISN mass scale and differs from the previous analysis. This analysis sheds light on the lower edge of the PISN mass scale of black holes and provides hints toward the formation channel of the BBH systems that are different from the usual fiducial scenario with a power-law index $d=-1$. Our results are consistent with the scenarios of varying (or fixed) Hubble constant and also for events with lower matched filtering network signal to noise ratio.

NASA will launch the Nancy Grace Roman Space Telescope (Roman) in the second half of this decade, which will allow for a generation-defining measurement of dark energy through multiple probes, including Type Ia supernovae (SNe Ia). To improve decisions on survey strategy, we have created the first simulations of realistic Roman images that include artificial SNe Ia injected as point sources in the images. Our analysis combines work done on Roman simulations for weak gravitational lensing studies as well as catalog-level simulations of SN samples. We have created a time series of images over two years containing $\sim$ 1,050 SNe Ia, covering a 1 square degree subarea of a planned 5 square degree deep survey. We have released these images publicly for community use along with input catalogs of all injected sources. We create secondary products from these images by generating coadded images and demonstrating recovery of transient sources using image subtraction. We perform first-use analyses on these images in order to measure galaxy-detection efficiency, point source-detection efficiency, and host-galaxy association biases. The simulated images can be found here: https://roman.ipac.caltech.edu/sims/SN_Survey_Image_sim.html.

To push the radial velocity (RV) exoplanet detection threshold, it is crucial to find more reliable radial velocity extraction methods. The Least-Squares Deconvolution (LSD) technique has been used to infer the stellar magnetic flux from spectropolarimetric data for the past two decades. It relies on the assumption that stellar absorption lines are similar in shape. Although this assumption is simplistic, LSD provides a good model for intensity spectra and likewise an estimate for their Doppler shift. We present the Multi-Mask Least-Squares Deconvolution (MM-LSD) RV extraction pipeline which extracts the radial velocity from two-dimensional echelle-order spectra using LSD with multiple tailored masks after continuum normalisation and telluric absorption line correction. The flexibility of LSD allows to exclude spectral lines or pixels at will, providing a means to exclude variable lines or pixels affected by instrumental problems. The MM-LSD pipeline was tested on HARPS-N data for the Sun and selected well-observed stars with 5.7 < Vmag < 12.6. For FGK-type stars with median signal-to-noise above 100, the pipeline delivered RV time series with on average 12 per cent lower scatter as compared to the HARPS-N RV extraction pipeline based on the Cross-Correlation Function technique. The MM-LSD pipeline may be used as a standalone RV code, or modified and extended to extract a proxy for the magnetic field strength.

Scale invariance is expected in empty Universe models, while the presence of matter tends to suppress it. As shown recently, scale invariance is certainly absent in cosmological models with densities equal to or above the critical value $\varrho_{\mathrm{c}} =3H^2_0/(8 \pi G)$. For models with densities below $\varrho_{\mathrm{c}}$, the possibility of limited effects remains open. If present, scale invariance would be a global cosmological property. Some traces could be observable locally. For the Earth-Moon two-body system, the predicted additional lunar recession would be increased by 0.92 cm/yr, while the tidal interaction would also be slightly increased. The Earth-Moon distance is the most systematically measured distance in the Solar System, thanks to the Lunar Laser Ranging (LLR) experiment active since 1970. The observed lunar recession from LLR amounts to 3.83 ($\pm 0.009$) cm/yr; implying a tidal change of the length-of-the-day (LOD) by 2.395 ms/cy. However, the observed change of the LOD since the Babylonian Antiquity is only 1.78 ms/cy, a result supported by paleontological data, and implying a lunar recession of 2.85 cm/yr. The significant difference of (3.83-2.85) cm/yr = 0.98 cm/yr, already pointed out by several authors over the last two decades, corresponds well to the predictions of the scale-invariant theory, which is also supported by several other astrophysical tests.

Halos of similar mass and redshift exhibit a large degree of variability in their differential properties, such as dark matter, hot gas, and stellar mass density profiles. This variability is an indicator of diversity in the formation history of these dark matter halos that is reflected in the coupling of scatters about the mean relations. In this work, we show that the strength of this coupling depends on the scale at which halo profiles are measured. By analyzing the outputs of the IllustrisTNG hydrodynamical cosmological simulations we report the radial- and mass-dependent couplings between the dark matter, hot gas, and stellar mass radial density profiles utilizing the population diversity in dark matter halos. We find that for the same mass halos the scatters in density of baryons and dark matter are strongly coupled at large scales ($r>R_{200}$); but the coupling between gas and dark matter density profiles fades near the core of halos ($r < 0.3 R_{200}$). We then show that the correlation between halo profile and integrated quantities induces a radius-dependent additive bias in the profile observables of halos when halos are selected on properties other than their mass. We discuss the impact of this effect on cluster abundance and cross-correlations cosmology with multi-wavelength cosmological surveys.

Microwave Kinetic Inductance Detectors (MKIDs) are highly scalable detectors that have demonstrated nearly background-limited sensitivity in the far-infrared from high-altitude balloon-borne telescopes and space-like laboratory environments. In addition, the detectors have a rich design space with many optimizable parameters, allowing highly sensitive measurements over a wide dynamic range. For these reasons, MKIDs were chosen for the Experiment for Cryogenic Large-Aperture Intensity Mapping (EXCLAIM), a balloon-borne telescope targeting nearly background-limited performance in a high-altitude atmospheric environment from 420-540 GHz. We describe MKID optimization in the specific context of EXCLAIM and provide general results that apply to broader applications. Extending the established approach of tone frequency tracking, we show that readout power optimization enables significant, further improvement in dynamic range.

We describe the data processing of the Survey on extragALactic magnetiSm with SOFIA (SALSA Legacy Program). This first data release presents 33% (51.34h out of 155.7h, including overheads) of the total awarded time taken from January 2020 to December 2021. Our observations were performed using the newly implemented on-the-fly mapping (OTFMAP) technique in the polarimetric mode. We present the pipeline steps to obtain homogeneously reduced high-level data products of polarimetric maps of galaxies for use in scientific analysis. Our approach has a general design and can be applied to sources smaller than the field-of-view of the HAWC+ array in any given band. We estimate that the OTFMAP polarimetric mode offers a reduction of observing overheads by a factor 2.34, and an improvement in sensitivity by a factor 1.80 when compared to previously obtained polarimetric observations using the chopping and nodding mode. The OTFMAP is a significant optimization of the polarimetric mode of HAWC+ as it ultimately reduces the cost of operations of SOFIA/HAWC+ by increasing the science collected per hour of observation up to an overall factor of 2.49. The OTFMAP polarimetric mode is the standard observing strategy of SALSA. The results and quantitative analysis of this first data release are presented in Papers IV and V of the series.

The star $\beta$ Pictoris harbors a young planetary system, which is characterized by the presence of a gaseous and dusty debris disk, at least two massive planets and many minor bodies. For more than thirty years, exocomets transiting the star have been detected using spectroscopy, probing the gaseous part of the cometary comas and tails. The detection of the dusty component of the tails can be performed through photometric observations of the transits. Since 2018, the Transiting Exoplanet Survey Satellite has observed $\beta$ Pic for a total of 156 days. Here we report an analysis of the TESS photometric data set with the identification of a total of 30 transits of exocomets. Our statistical analysis shows that the number of transiting exocomet events ($N$) as a function of the absorption depth ($AD$) in the light curve follows a power law in the form $dN(AD) \propto AD^{-\alpha}$, where $\alpha=2.3\pm 0.4$. This distribution of absorption depth leads to a differential comet size distribution proportional to $R^{-\gamma}$, where $\gamma =3.6 \pm 0.8$, showing a striking similarity to the size distribution of comets in the Solar system and the distribution of a collisionally relaxed population ($\gamma_{\rm D}= 3.5$).

We give an updated version of the analytical equation of state used in the Cambridge stellar evolution code (STARS) as a free to use open-source package that we have used to model cool white dwarfs down to temperatures $\log_{10}(T_\mathrm{eff}/\mathrm{K})\:=\;3$. With this update in the STARS code we model the secular evolution of cataclysmic variable (CV) stars using a double dynamo model wherein there is an interplay between two $\alpha-\Omega$ dynamos, one in the convective envelope and the other at the boundary of a slowly rotating shrinking radiative core and the growing convective envelope. We confirm that this model provides a physical formalism for the interrupted magnetic braking paradigm. In addition, our model also provides a mechanism for extra angular momentum loss below the period gap. We construct the relative probability distribution of orbital periods $P_\mathrm{orb}$ using the {mass} distribution of white dwarfs in cataclysmic variables and find that our model excellently reproduces the period gap and the observed period minimum spike in CV distribution. We also compare the evolutionary trajectories from our model with those of other empirical models and find agreement between the two. We also report good agreement between our modelled systems and observational data.

We present the analysis of the halo bispectrum in redshift-space in terms of its multipoles, monopole, quadrupole and hexadecapole, measured from a large set of simulations. We fit such measurements with a tree-level model in perturbation theory that depends on linear and nonlinear bias parameters as well as on the growth rate $f$ of density fluctuations. The likelihood analysis takes advantage of a very large set of mock catalogs, enabling a robust estimation of the covariance properties for all multipoles. We compare the numerical estimate of the covariance matrix to its Gaussian prediction finding discrepancies of 10% or less for all configurations with the sole exception of the squeezed triangles in the monopole case. We find the range of validity of the tree-level model, for the total simulation volume of about 1000 $h^{-3}\, {\rm Gpc}^3$, reaches a maximum wavenumber of $0.08 \, h \, {\rm Mpc}^{-1}$ for the monopole, while it is limited to $0.06$ and $0.045\, h \, \rm{Mpc}^{-1}$ respectively for quadrupole and hexadecapole. Despite this, the addition of the quadrupole to the analysis allows for significant improvements on the determination of the model parameters and specifically on $f$, similarly to the power spectrum case. Finally, we compare our numerical estimate for the full covariance with its theoretical prediction in the Gaussian approximation and find the latter to work remarkably well in the context of simulation boxes with periodic boundary condition.

This work presents an extensive analysis of the properties of three southern semi-detached eclipsing binaries hosting a pulsating component, namely HM Pup, V632 Sco, and TT Vel. Systematic multi-filtered photometric observations were obtained using telescopes located in Australia and Chile mostly between 2018-2021. These observations were combined with data from the Transiting Exoplanet Survey Satellite (TESS) mission for a detailed analysis of pulsations. Spectral types and radial velocities were determined from spectra obtained with the Australian National University's 2.3 m telescope and Wide Field Spectrograph. The data are modelled and the absolute parameters of all components are derived. The light curve residuals are further analysed using Fourier transformation techniques for the determination of the pulsation frequencies. Using theoretical models, the most probable modes of the principal oscillations are also identified. Eclipse-timing variation analysis is also made for all systems and the most likely mechanisms modulating the orbital period are proposed. The physical properties of these systems are compared with other similar cases and the locations of their components are plotted in the M-R and HR diagrams. Finally, the pulsational properties of the oscillating components are compared with currently known systems of this type within the orbital-pulsation period and log g-pulsation period diagrams. These systems are identified as oEA stars by definition, with the primaries to be pulsating stars of $\delta$ Scuti type, while evidence of mass flow from the evolved secondary components is present in their Na I D spectra.

We present the first Active Galactic Nuclei (AGN) catalog in the Hobby-Eberly Telescope Dark Energy Experiment Survey (HETDEX) observed between January 2017 and June 2020. HETDEX is an ongoing spectroscopic survey with no pre-selection based on magnitudes, colors or morphologies, enabling us to select AGN based on their spectral features. Both luminous quasars and low-luminosity Seyferts are found in our catalog. AGN candidates are selected with at least two significant AGN emission lines, such as the LyA and CIV line pair, or with single broad emission lines (FWHM > 1000 km/s). Each source is further confirmed by visual inspections. This catalog contains 5,322 AGN, covering an effective sky coverage of 30.61 deg^2. A total of 3,733 of these AGN have secure redshifts, and we provide redshift estimates for the remaining 1,589 single broad-line AGN with no cross matched spectral redshifts from SDSS DR14Q. The redshift range of the AGN catalog is 0.25 < z < 4.32, with a median of z = 2.1. The bolometric luminosity range is 10^9-10^14 Lsun with a median of 10^12 Lsun. The median r-band magnitude of the AGN is 21.6 mag, with 34% of the AGN have r > 22.5, and 2.6% reaching the detection limit at r ~ 26 mag of the deepest imaging surveys we searched. We also provide a composite spectrum of the AGN sample covering 700 AA - 4400 AA.

Microwave Kinetic Inductance Detectors (MKIDs) sensitive to light in the ultraviolet to near-infrared wavelengths are superconducting micro-resonators that are capable of measuring photon arrival times to microsecond precision and estimating each photon's energy. The resolving power of non-membrane MKIDs has remained stubbornly around 10 at 1 $\mu$m despite significant improvements in the system noise. Here we show that the resolving power can be roughly doubled with a simple bilayer design without needing to place the device on a membrane, avoiding a significant increase in fabrication complexity. Based on modeling of the phonon propagation, we find that the majority of the improvement comes from the inability of high energy phonons to enter the additional layer due to the lack of available phonon states.

We map the 3D kinematics of the Galactic disc out to 3.5 kpc from the Sun, and within 0.75 kpc from the midplane of the Milky Way. To this end, we combine high quality astrometry from \gedrthree{}, with the radial velocities from \gdrtwo{}, and from major spectroscopic surveys including \apogee{}, \galah{}, and \lamost{}. We construct an axisymmetric model for the mean velocity field, and then subtract this on a star-by-star basis to obtain the peculiar velocity field in the Galactocentric components, \vphi{}, \vR, \vz, as well as the heliocentric line-of-sight, \vlos{}. The velocity residuals are quantified using the power spectrum, and we find that the peak power ($A$) in the midplane ($|z|<0.25$ kpc) is ($A_{\phi},A_{\rm R},A_{\rm Z},A_{\rm los}$)=($4.2,8.5,2.6,4.6$), at $0.25 < |z|/[{\rm kpc}] < 0.5$, is ($A_{\phi},A_{\rm R},A_{\rm Z},A_{\rm los}$)=($4.0,7.9,3.6,5.3$), and at $0.5 < |z|/[{\rm kpc}] < 0.75$, is ($A_{\phi},A_{\rm R},A_{\rm Z},A_{\rm los}$)=($1.9,6.9,5.2,6.4$). Our results provide for the first time, a measure of the streaming motion in the disc in the individual components. We find that streaming is most significant in the Galactocentric radial component, and at all heights ($|Z|$) probed, but is also not negligible in the other components. Additionally, we find that the patterns in the velocity field overlap spatially with models for the Spiral arms in the Milky Way. Finally, we demonstrate using a simulation that phase mixing of disrupting spiral arms can generate such residuals in the velocity field, where the radial component is dominant, just as in the real data. The simulation also suggests that with evolution of time both the amplitude and the physical scale of the peculiar motion decreases.

We explore the use of observed polar coronal holes (CHs) to constrain the flux distribution within the polar regions of global solar magnetic field maps in the absence of reliable quality polar field observations. Global magnetic maps, generated by the Air Force Data Assimilative Photospheric flux Transport (ADAPT) model, are modified to enforce field unipolarity thresholds both within and outside observed CH boundaries. The polar modified and unmodified maps are used to drive Wang-Sheeley-Arge (WSA) models of the corona and solar wind (SW). The WSA predicted CHs are compared with the observations, and SW predictions at the WIND and Ulysses spacecraft are also used to provide context for the new polar modified maps. We find that modifications of the polar flux never worsen and typically improve both the CH and SW predictions. We also confirm the importance of the choice of the domain over which WSA generates the coronal magnetic field solution but find that solutions optimized for one location in the heliosphere can worsen predictions at other locations. Finally, we investigate the importance of low-latitude (i.e., active region) magnetic fields in setting the boundary of polar CHs, determining that they have at least as much impact as the polar fields themselves.

In this work, we revisit the Witten-O'Raifeartaigh model of inflation, in which the potential takes a $\operatorname{log}^2(\phi/M)$ form, when the scalar field is non-minimally coupled to gravity. We investigate the impact of the coupling in the prediction of the inflationary parameters, thereby affecting the viability of the model. We find that a small coupling of order $\xi\sim10^{-3}$ is preferred by data at the $n_s-r$ plane level, and that the presence of a non-zero $\xi$ allows for a large interval of the mass scale $M$, in which it is possible to achieve a low tensor-to-scalar ratio. We also establish constraints imposed by a subsequent reheating era, in which its duration and temperature can be related to CMB observables, which in return, restricts the possible values for the $n_s$ and $r$ parameters.

The terminal wall velocity of a first-order phase transition bubble can be calculated from a set of fluid equations describing the scalar fields and the plasma's state. We rederive these equations from the energy-momentum tensor conservation and the Boltzmann equation, without linearizing in the background temperature and fluid velocity. The resulting equations have a finite solution for any wall velocity. We propose a spectral method to integrate the Boltzmann equation, which is simple, efficient and accurate. As an example, we apply this new methodology to the singlet scalar extension of the standard model. We find that all solutions are naturally categorized as deflagrations ($v_w\sim c_s$) or ultrarelativistic detonations ($\gamma_w\gtrsim10$). Furthermore, the contributions from out-of-equilibrium effects are, most of the time, subdominant. Finally, we use these results to propose several approximation schemes with increasing levels of complexity and accuracy. They can be used to considerably simplify the methodology while correctly describing the qualitative behavior of the bubble wall.

The Gauss-Bonnet curvature invariant has attracted the attention of physicists and mathematicians over the years. In particular, it has recently been proved that black holes can support external matter configurations that are non-minimally coupled to the Gauss-Bonnet invariant of the curved spacetime. Motivated by this physically interesting behavior of black holes in Einstein-Gauss-Bonnet theories, we present a detailed {\it analytical} study of the physical and mathematical properties of the Gauss-Bonnet curvature invariant ${\cal G}_{\text{Kerr}}(r,\cos\theta;a/M)$ of spinning Kerr black holes in the spacetime region outside the horizon. Interestingly, we prove that, for all spinning Kerr spacetimes in the physically allowed regime $a/M\in[0,1]$, the spin-dependent maximum curvature of the Gauss-Bonnet invariant is attained at the equator of the black-hole surface. Intriguingly, we reveal that the location of the global minimum of the Gauss-Bonnet invariant has a highly non-trivial functional dependence on the black-hole rotation parameter: (i) For Kerr black holes in the dimensionless slow-rotation $a/M<(a/M)^{-}_{\text{crit}}=1/2$ regime, the Gauss-Bonnet curvature invariant attains its global minimum asymptotically at spatial infinity, (ii) for black holes in the intermediate spin regime $1/2=(a/M)^{-}_{\text{crit}}\leq a/M\leq(a/M)^{+}_{\text{crit}}= \sqrt{\Big\{{{7+\sqrt{7}\cos\Big[3^{-1}\arctan\big(3\sqrt{3}\big)\Big]- \sqrt{21}\sin\Big[3^{-1}\arctan\big(3\sqrt{3}\big)\Big]\Big\}}/12}}$, the global minima are located at the black-hole poles, and (iii) Kerr black holes in the super-critical regime $a/M>(a/M)^{+}_{\text{crit}}$ are characterized by a non-trivial functional behavior of the Gauss-Bonnet curvature invariant along the black-hole horizon with a spin-dependent polar angle for the global minimum point.

We discuss the formation of cosmic strings or macroscopic color flux tubes at the phase transition from the deconfinement to confinement phase in pure Yang-Mills (YM) theory, such as SU($N$), Sp($N$), SO($N$), and Spin($N$), based on the current understanding of theoretical physics. According to the holographic dual descriptions, the cosmic strings are dual to fundamental strings or wrapped D-branes in the gravity side depending on the structure of the gauge group, and the reconnection probability is suppressed by $\mathcal{O}(N^{-2})$ and $e^{-\mathcal{O}(N)}$, respectively. The pure YM theory thus provides a simple realization of cosmic F- and D-strings without the need for a brane-inflationary scenario or extra dimension. We also review the stability of cosmic strings based on the concept of 1-form symmetry, which further implies the existence of a baryon vertex in some YM theory. We calculate the gravitational wave spectrum that is emitted from the cosmic strings based on an extended velocity-dependent one-scale model and discuss its detectability based on ongoing and planned gravitational-wave experiments. In particular, the SKA and LISA can observe gravitational signals if the confinement scale is higher than $\mathcal{O}(10^{12})\,\mathrm{GeV}$ and $\mathcal{O}(10^{10})\,\mathrm{GeV}$ for SU($N$) with $N = \mathcal{O}(1)$, respectively.

We exhibit a mechanism which dynamically adjusts cosmological constant toward $0^+$. The adjustment is quantum-mechanical, discharging cosmological constant in random discrete steps. It renders de Sitter space unstable, and triggers its decay toward Minkowski. Since the instability dynamically stops at $\Lambda = 0$, the evolution favors the terminal Minkowski space without a need for anthropics. The mechanism works for any QFT coupled to gravity.

We discuss the formation of cosmic strings or macroscopic color flux tubes after the deconfinement/confinement phase transition in the pure Yang-Mills theory. Based on holographic dual descriptions, these cosmic strings can be interpreted as fundamental (F-) strings or wrapped D-branes (which we call as D-strings) in the gravity side, depending on the structure of the gauge group. In fact, the reconnection probabilities of the F- and D-strings are suppressed by factors of $1/N^2$ and $e^{-c N}$, where $c = \mathcal{O}(1)$, in a large-$N$ limit, respectively. Supported by the picture of electric-magnetic duality, we discuss that color flux tubes form after the deconfinement/confinement phase transition, just like the formation of local cosmic strings after spontaneous symmetry breaking in the weak-U(1) gauge theory. We use an extended velocity-dependent one-scale model to describe the dynamics of the string network and calculate the gravitational wave signals from string loops.

One of the few remaining unknowns in the standard three-flavor neutrino oscillation paradigm is the ordering of neutrino masses. In this work we propose a novel method for determining neutrino mass ordering using the time information on early supernova neutrino events. In a core-collapse supernova, neutrinos are produced earlier than antineutrinos and, depending on the mass ordering which affects the adiabatic flavor evolution, may cause earlier observable signals in $\nu_e$ detection channels than in others. Hence, the time differences are sensitive to the mass ordering. We find that using the time information on the detection of the first galactic supernova events at future detectors like DUNE, JUNO and Hyper-Kamiokande, the mass ordering can already be determined at 2$\sigma$ CL, while $\mathcal{O}(10)$ events suffice for the discovery. Our method does not require high-statistics and could be used within the supernova early warning system (SNEWS) which will have access to the time information on early supernova neutrino events recorded in a number of detectors. The method proposed in this paper also implies a crucial interplay between the mass ordering and the triangulation method for locating supernovae.

The Peak-Patch algorithm is used to identify the densest minicluster seeds in the initial axion density field simulated from string decay. The fate of these dense seeds is found by tracking the subsequent gravitational collapse in cosmological $N$-body simulations. We find that miniclusters at late times are well described by NFW profiles, although for around 70\% of simulated miniclusters a single power law density profile of $r^{-2.9}$ is an equally good fit due to the unresolved scale radius. Under the assumption that all miniclusters with an unresolved scale radius are described by a power-law plus axion star density profile, we identify a significant number of miniclusters that might be dense enough to give rise to gravitational microlensing if the axion mass is $0.2 \,\mathrm{meV}\lesssim m_a \lesssim 3\,\mathrm{meV}$. Higher resolution simulations resolving the inner structure and axion star formation are necessary to explore this possibility further.

There are at present ${\cal O}(100)$ gravitational-wave candidates from compact binary mergers reported in the astronomical literature. As detector sensitivities are improved, the catalog will swell in size: first to ${\cal O}(1000)$ events in the A+ era and then to ${\cal O}(10^6)$ events in the era of third-generation observatories like Cosmic Explorer and the Einstein Telescope. Each event is analyzed using Bayesian inference to determine properties of the source including component masses, spins, tidal parameters, and the distance to the source. These inference products are the fodder for some of the most exciting gravitational-wave science, enabling us to measure the expansion of the Universe with standard sirens, to characterise the neutron star equation of state, and to unveil how and where gravitational-wave sources are assembled. In order to maximize the science from the coming deluge of detections, we introduce GWCloud, a searchable repository for the creation and curation of gravitational-wave inference products. It is designed with five pillars in mind: uniformity of results, reproducibility of results, stability of results, access to the astronomical community, and efficient use of computing resources. We describe how to use GWCloud with examples, which readers can replicate using the companion code to this paper. We describe our long-term vision for GWCloud.

We study the synchrotron radio emission in the mixed dark matter scenarios consisting of the primordial black holes (PBHs) and the self-annihilating WIMPs (weakly interacting massive particles). The WIMPs can form the ultracompact minihalos around PBHs and the annihilation enhancement from these dense halos can lead to the efficient synchrotron radiation at the radio frequency in the presence of galactic magnetic fields. The upper bound of PBH fraction with respect to the total dark matter abundance is of order $10^{-8}\sim 10^{-5}$ depending on the electroweak scale WIMP mass ($m_{\chi}=10\sim 1000$ GeV) and the WIMP annihilation channel (e.g. a hadronic $\chi \chi \rightarrow b \bar{b}$ or a leptonic $\chi \chi \rightarrow e^+ e^-$ channel). The PBH contribution to the total dark matter abundance is hence negligible when the other component of dark matter is composed of the conventional electroweak scale WIMPs.

We study a mechanism through which the cosmic dark matter density can be explained simultaneously with the observed baryon asymmetry of the Universe. At the core of our proposal lie the out-of-equilibrium scattering processes of bath particles which are responsible for the production of feebly-interacting dark matter. The same processes violate $CP$, which further leads to an asymmetry between matter and antimatter being generated in the visible sector. We focus on the possibility that these interactions are described through non-renormalizable operators, which leads to both dark matter and the baryon asymmetry being produced at high temperatures. The mechanism is exemplified by studying two concrete scenarios, one involving scalar and one involving fermion dark matter. We find that in both cases it is, indeed, possible to achieve a common explanation for the dark matter content and the matter-antimatter asymmetry of the Universe, provided that dark matter is in the keV mass range.