Sazuna/UAT_keywords huggingface dataset:
Reoriented Memory of Galaxy Spins for the Early Universe. Galaxy spins are believed to retain the initially acquired tendency of being aligned with the intermediate principal axis of the linear tidal field, which disseminates the prospect of using them as a probe of early universe physics. This roseate prospect, however, is contingent upon the key assumption that the observable stellar spins of present galaxies measured at inner radii have the same alignment tendency toward the initial tidal field as their dark matter counterparts measured at virial limits. We test this assumption directly against a high-resolution hydrodynamical simulation by tracing the galaxy component particles back to the protogalactic stage. It is discovered that the galaxy stellar spins at z = 0 have strong but reoriented memory for the early universe, exhibiting a significant signal of cross-correlation with the major principal axis of the initial tidal field at z = 127. An analytic single-parameter model for this reorientation of the present galaxy stellar spins relative to the initial tidal field is devised and shown to be in good accord with the numerical results.

Keywords: Cosmology, Large-scale structure of the universe
Structure of the W3A Low-density Foreground Region. We present analysis of [O I] 63 μm and CO J = 5 - 4 and 8 - 7 multiposition data in the W3A region and use it to develop a model for the extended low-density foreground gas that produces absorption features in the [O I] and J = 5 - 4 CO lines. We employ the extinction to the exciting stars of the background H II region to constrain the total column density of the foreground gas. We have used the Meudon photodissociation region code to model the physical conditions and chemistry in the region employing a two-component model with a high-density layer near the H II region responsible for the fine-structure line emission and an extended low-density foreground layer. The best-fitting total proton density, constrained largely by the CO lines, is n(H) = 250 cm-3 in the foreground gas and 5 × 105 cm-3 in the material near the H II region. The absorption is distributed over the region mapped in W3A and is not restricted to the foreground of either the embedded exciting stars of the H II region or the protostar W3 IRS5. The low-density material associated with regions of massive-star formation, based on an earlier study by Goldsmith et al., is quite common, and we now see that it is extended over a significant portion of W3A. It thus should be included in modeling of fine-structure line emission, including interpreting low-velocity-resolution observations made with incoherent spectrometer systems, in order to use these lines as accurate tracers of massive-star formation.

Keywords: Submillimeter astronomy, Giant molecular clouds, Star formation, Photodissociation regions
A Stability Timescale for Nonhierarchical Three-body Systems. The gravitational three-body problem is a fundamental problem in physics and has significant applications to astronomy. Three-body configurations are often considered stable as long the system is hierarchical; that is, the two orbital distances are well-separated. However, instability, which is often associated with significant energy exchange between orbits, takes time to develop. Assuming two massive objects in a circular orbit and a test particle in an eccentric orbit, we develop an analytical formula estimating the time it takes for the test particle's orbital energy to change by an order of itself. We show its consistency with results from N-body simulations. For eccentric orbits in particular, the instability is primarily driven not by close encounters of the test particle with one of the other bodies, but by the fundamental susceptibility of eccentric orbits to exchange energy at their periapsis. Motivated by recent suggestions that the galactic center may host an intermediate-mass black hole (IMBH) as a companion to the massive black hole Sgr A*, we use our timescale to explore the parameter space that could harbor an IMBH for the lifetime of the S-cluster of stars surrounding Sgr A*. Furthermore, we show that the orbit of an S-star can be stable for long timescales in the presence of other orbital crossing stars, thus suggesting that the S-cluster may be stable for the lifetimes of its member stars.

Keywords: Intermediate-mass black holes, Supermassive black holes, Galactic center, Black holes, High energy astrophysics, Exoplanets, Three-body problem, Galaxies
Looking for Traces of Nonminimally Coupled Dark Matter in the X-COP Galaxy Clusters Sample. We look for possible evidence of a nonminimal coupling (NMC) between dark matter (DM) and gravity using data from the X-COP compilation of galaxy clusters. We consider a theoretically motivated NMC that may dynamically arise from the collective behavior of the coarse-grained DM field (e.g., via Bose-Einstein condensation) with averaging/coherence length L NMC. In the Newtonian limit, the NMC modifies the Poisson equation by a term ${L}_{\mathrm{NMC}}^{2}{{\rm{\nabla }}}^{2}\rho $ proportional to the Laplacian of the DM density itself. We show that this term, when acting as a perturbation over the standard Navarro-Frenk-White (NFW) profile of cold DM particles, can yield DM halo density profiles capable of correctly fitting galaxy clusters' pressure profiles with an accuracy comparable to and, in some cases, even better than the standard cold DM NFW profile. We also show that the observed relation between the NMC length scale and the virial mass found in Gandolfi et al. for late-type galaxies is consistent with the relation we find in the current work, suggesting that the previously determined power-law scaling law holds up to galaxy cluster mass scales.

Keywords: Galaxy clusters, Cosmology, Non-standard theories of gravity, Cold dark matter, Dark matter
RAM: Rapid Advection Algorithm on Arbitrary Meshes. The study of many astrophysical flows requires computational algorithms that can capture high Mach number flows, while resolving a large dynamic range in spatial and density scales. In this paper we present a novel method, RAM: Rapid Advection Algorithm on Arbitrary Meshes. RAM is a time-explicit method to solve the advection equation in problems with large bulk velocity on arbitrary computational grids. In comparison with standard upwind algorithms, RAM enables advection with larger time steps and lower truncation errors. Our method is based on the operator splitting technique and conservative interpolation. Depending on the bulk velocity and resolution, RAM can decrease the numerical cost of hydrodynamics by more than one order of magnitude. To quantify the truncation errors and speed-up with RAM, we perform one- and two-dimensional hydrodynamics tests. We find that the order of our method is given by the order of the conservative interpolation and that the effective speed-up is in agreement with the relative increment in time step. RAM will be especially useful for numerical studies of disk-satellite interaction, characterized by high bulk orbital velocities and nontrivial geometries. Our method dramatically lowers the computational cost of simulations that simultaneously resolve the global disk and potential well inside the Hill radius of the secondary companion.

Keywords: Accretion, Protoplanetary disks, Algorithms, Hydrodynamics
Molecular Environment of the Thermal Composite Supernova Remnant G352.7-0.1. Galactic supernova remnants (SNRs) play an important role in our understanding of supernovae and their feedback on the interstellar environment. SNR G352.7-0.1 is special for its thermal composite morphology and double-ring structure. We have performed spectroscopic mapping of the 12CO and 13CO J = 2-1 lines toward G352.7-0.1 with the Atacama Pathfinder Experiment telescope. Broad 12CO lines are found in the northeastern ring at a local-standard-of-rest velocity range of ~-50 to -30 km s-1, suggesting that the remnant is interacting with molecular clouds at ~-51 km s-1. Thus, we adopt a distance of ~10.5 kpc for this SNR. The momentum and kinetic energy of the shocked gas along the line of sight are estimated to be ~102 M ☉ km s-1 and ~1046 erg, respectively. We also find an expanding structure around the remnant, which is possibly related to the wind-blown bubble of the progenitor star. From Fermi-LAT data in the energy range 0.1-500 GeV, we find no gamma-ray counterparts to G352.7-0.1.

Keywords: Supernova remnants, Shocks, Molecular clouds, Interstellar medium
Substructures in Compact Disks of the Taurus Star-forming Region. Observations of substructure in protoplanetary disks have largely been limited to the brightest and largest disks, excluding the abundant population of compact disks, which are likely sites of planet formation. Here, we reanalyze ~0.″1, 1.33 mm Atacama Large Millimeter/submillimeter Array (ALMA) continuum observations of 12 compact protoplanetary disks in the Taurus star-forming region. By fitting visibilities directly, we identify substructures in six of the 12 compact disks. We then compare the substructures identified in the full Taurus sample of 24 disks in single-star systems and the ALMA DSHARP survey, differentiating between compact (R eff,90% &lt; 50 au) and extended (R eff,90% ≥50 au) disk sources. We find that substructures are detected at nearly all radii in both small and large disks. Tentatively, we find fewer wide gaps in intermediate-sized disks with R eff,90% between 30 and 90 au. We perform a series of planet-disk interaction simulations to constrain the sensitivity of our visibility-fitting approach. Under the assumption of planet-disk interaction, we use the gap widths and common disk parameters to calculate potential planet masses within the Taurus sample. We find that the young planet occurrence rate peaks near Neptune masses, similar to the DSHARP sample. For 0.01 M J/M ⊙ ≲M p/M * ≲0.1 M J/M ⊙, the rate is 17.4% ± 8.3%; for 0.1 M J/M ⊙ ≲M p/M * ≲1 M J/M ⊙, it is 27.8% ± 8.3%. Both of them are consistent with microlensing surveys. For gas giants more massive than 5 M J, the occurrence rate is 4.2% ± 4.2%, consistent with direct imaging surveys.

Keywords: Planetary-disk interactions, Protoplanetary disks, Exoplanet systems
The Spatial Clustering of ROSAT All-Sky Survey Active Galactic Nuclei. V. The Evolution of Broad-line AGN Clustering Properties in the Last 6 Gyr. This is the fifth paper in a series of investigations of the clustering properties of luminous, broad-emission-line active galactic nuclei (AGNs) identified in the ROSAT All-Sky Survey (RASS) and Sloan Digital Sky Survey (SDSS). In this work we measure the cross-correlation function (CCF) between RASS/SDSS Data Release 14 AGNs with the SDSS CMASS galaxy sample at 0.44 &lt; z &lt; 0.64. We apply halo occupation distribution (HOD) modeling to the CCF along with the autocorrelation function of the CMASS galaxies. We find that X-ray-selected and optically selected AGNs at 0.44 &lt; z &lt; 0.64 reside in statistically identical halos with a typical dark matter halo (DMH) mass of ${M}_{\mathrm{DMH}}^{\mathrm{typ},\mathrm{AGN}}\sim {10}^{12.7}\,{h}^{-1}\,{M}_{\odot }$ . The acceptable HOD parameter space for these two broad-line AGN samples have only statistically marginal differences caused by small deviations of the CCFs in the one-halo-dominated regime on small scales. In contrast to optically selected AGNs, the X-ray AGN sample may contain a larger population of satellites at M DMH ~ 1013 h -1 M ⊙. We compare our measurements in this work with our earlier studies at lower independent redshift ranges, spanning a lookback time of 6 Gyr. The comparison over this wider redshift range of 0.07 &lt; z &lt; 0.64 reveals (i) no significant difference between the typical DMH masses of X-ray-selected and optically selected AGNs, (ii) weak positive clustering dependencies of ${M}_{\mathrm{DMH}}^{\mathrm{typ},\mathrm{AGN}}$ with L X and M BH, (iii) no significant dependence of ${M}_{\mathrm{DMH}}^{\mathrm{typ},\mathrm{AGN}}$ on Eddington ratio, and (iv) the same DMH masses host more-massive accreting black holes at high redshift than at low redshifts.

Keywords: Active galaxies, X-ray active galactic nuclei, Large-scale structure of the universe
Introducing the Texas Euclid Survey for Lyα (TESLA) Survey: Initial Study Correlating Galaxy Properties to Lyα Emission. We present the Texas Euclid Survey for Lyα (TESLA), a spectroscopic survey in the 10 deg2 of the Euclid North Ecliptic Pole (NEP) field. Using TESLA, we study how the physical properties of Lyα emitters (LAEs) correlate with Lyα emission to understand the escape of Lyα emission from galaxies at redshifts of 2-3.5. We present an analysis of 43 LAEs performed in the NEP field using early data from the TESLA survey. We use Subaru Hyper Suprime-Cam imaging in the grizy bands, Spitzer/IRAC channels 1 and 2 from the Hawaii 20 deg2 (H20) survey, and spectra acquired by the Visible Integral-Field Replicable Unit Spectrograph (VIRUS) on the Hobby-Eberly Telescope. We perform spectral energy distribution (SED) fitting to compute the galaxy properties of 43 LAEs, and study correlations between stellar mass, star formation rate (SFR), and dust to the Lyα rest-frame equivalent width (W Lyα ). We uncover marginal (1σ significance) correlations between stellar mass and W Lyα , and SFR and W Lyα , with a Spearman correlation coefficient of -0. ${34}_{-.14}^{+.17}$ and -0. ${37}_{-.14}^{+.16}$ , respectively. We show that the W Lyα  distribution of the 43 LAEs is consistent with being drawn from an exponential distribution with an e-folding scale of W 0 = 150 Å. Once complete the TESLA survey will enable the study of ≳50,000 LAEs to explore more correlations between galaxy properties and W Lyα . The large sample size will allow the construction of a predictive model for W Lyα  as a function of SED-derived galaxy properties, which could be used to improve Lyα-based constraints on reionization.

Keywords: Surveys, Reionization, Lyman-alpha galaxies, Galaxies
Prediction Capability of Geomagnetic Events from Solar Wind Data Using Neural Networks. Multiple neural network architectures, with different structural composition and complexity, are implemented in this study with the aim of providing multi-hour-ahead warnings of severe geomagnetic disturbances, based on in situ measurements of the solar wind plasma and magnetic field acquired at the Lagrangian point L1. First, a statistical analysis of the interplanetary data was performed to point out which are the most relevant parameters to be provided as input to the neural networks, and a preprocessing of the data set was implemented to face its heavy imbalance (the Earth's magnetosphere is in fact mostly at rest). Then, neural networks were tested to evaluate their performance. It turned out that, in a binary classification problem, recurrent approaches are best at predicting critical events both 1 and 8 hr in advance, achieving a balanced accuracy of 94% and 70%, respectively. Finally, in an attempt at multistep prediction of the criticality of future geomagnetic events from 1-8 hr ahead, more complex neural networks, built by merging the different types of basic convolutional and recurrent architectures, have been shown to outperform single-step and state-of-the-art approaches with a balanced accuracy of at least 70%. Interestingly, the accuracy peaks at 4 hr, corresponding to the waiting time between the detection of solar drivers at L1 and the onset of the geomagnetic storm (as previously obtained by statistical investigations), suggesting that on average this is the time the Earth's magnetosphere takes to react to the solar event.

Keywords: Geomagnetic fields, Heliosphere, Neural networks, Solar wind, Solar coronal mass ejections, Solar-terrestrial interactions, Solar storm
Identifying the Gamma-Ray Emission of the Nearby Galaxy M83. We report on the detection of a γ-ray source at the position of the nearby star-forming galaxy (SFG) M83, which is found from our analysis of 14 yr of the data obtained with the Large Area Telescope on board the Fermi Gamma-ray Space Telescope (Fermi). The source is weakly detected, with a significance of ~5σ, and its emission can be described with an exponentially cutoff power law. At a distance of 4.61 Mpc, the source's γ-ray luminosity is ~1.4 × 1039 erg s-1, roughly along the correlation line between the γ-ray and IR luminosities determined for nearby SFGs. Because of the weak detection, the source spectrum can not be used for checking its similarity with those of other SFGs. Given the positional matches and the empirical expectation for γ-ray emission from M83 due to the galaxy's star-forming activity, we conclude that the γ-ray source is the likely counterpart to M83. The detection thus adds another member to the group of approximately a dozen SFGs, whose γ-ray emissions mostly have a cosmic-ray origin.

Keywords: Gamma-ray sources, Starburst galaxies
Don't Believe the Hype(r): The Yellow Supergiants of Westerlund 1. Yellow hypergiants (YHGs) are often presumed to represent a transitional post-red supergiant (RSG) phase for stars ~30-40 M ☉. Here we present visual-wavelength echelle spectra of six YHG candidates in the Galactic cluster Westerlund 1, and we compare them to known YHGs, IRC +10420 and Hen 3-1979. We find that the six YHG candidates do not exhibit any metal emission lines, nor do they show strong Hα emission, and as such do not meet the criteria necessary to be classified as YHGs. In conjunction with their moderate luminosities of $\mathrm{log}(L/{L}_{\odot })$ = 4.7-5.4 estimated from optical/infrared photometry, we suggest instead that they are normal yellow supergiants (YSGs) with more modest initial masses around 15-20 M ☉. This adds additional support to the hypothesis that Wd1 is a multiage cluster with an older age than previously assumed, and is not a ~5 Myr old cluster caught at a very specific transitional point when single-star evolution might yield Wolf-Rayet stars, luminous blue variables, RSGs, and YHGs in the same cluster. Nevertheless, the population of YSGs in Wd1 is very unusual, with YSGs outnumbering RSGs, but with both spanning a large luminosity range. Here, we discuss evolutionary scenarios that might have led to the high fraction of YSGs. The number of YSGs and their significant luminosity spread cannot be explained by simple population synthesis models with single or binary stars. Even with multiple ages or a large age spread, the high YSG/RSG ratio remains problematic. We suggest instead that the objects may experience a prolonged YSG phase due to evolution in triple systems.

Keywords: Massive stars, Supergiant stars, Stellar evolution
Multiwavelength Characterization of the High-mass X-Ray Binary Population of M33. We present multiwavelength characterization of 65 high-mass X-ray binary (HMXB) candidates in M33. We use the Chandra ACIS survey of M33 (ChASeM33) catalog to select hard X-ray point sources that are spatially coincident with UV-bright point-source optical counterparts in the Panchromatic Hubble Andromeda Treasury: Triangulum Extended Region catalog, which covers the inner disk of M33 at near-IR, optical, and near-UV wavelengths. We perform spectral energy distribution fitting on multiband photometry for each point-source optical counterpart to measure its physical properties including mass, temperature, luminosity, and radius. We find that the majority of the HMXB companion star candidates are likely B-type main-sequence stars, suggesting that the HMXB population of M33 is dominated by Be X-ray binaries (Be-XRBs), as is seen in other Local Group galaxies. We use spatially resolved recent star formation history maps of M33 to measure the age distribution of the HMXB candidate sample and the HMXB production rate for M33. We find a bimodal distribution for the HMXB production rate over the last 80 Myr, with a peak at ~10 and ~40 Myr, which match theoretical formation timescales for the most massive HMXBs and Be-XRBs, respectively. We measure an HMXB production rate of 107-136 HMXBs/(M ☉ yr-1) over the last 50 Myr and 150-199 HMXBs/(M ☉ yr-1) over the last 80 Myr. For sources with compact object classifications from overlapping NuSTAR observations, we find a preference for giant/supergiant companion stars in black hole HMXBs and main-sequence companion stars in neutron star HMXBs.

Keywords: X-ray binary stars, Binary stars, Massive stars, High mass x-ray binary stars, Triangulum Galaxy
Radiative Acceleration of Dense Circumstellar Material in Interacting Supernovae. Early-time light curves/spectra of some hydrogen-rich supernovae (SNe) provide solid evidence of the existence of confined, dense circumstellar matter (CSM) surrounding dying massive stars. We numerically and analytically study the radiative acceleration of CSM in such systems, where the radiation is mainly powered by the interaction between the SN ejecta and the CSM. We find that the acceleration of the unshocked dense CSM ahead of the shock is larger for massive and compact CSM, with velocities reaching up to ~103 km s-1 for a CSM of order 0.1 M ⊙ confined within ~1015 cm. We show that the dependence of the acceleration on the CSM density helps us explain the diversity of the CSM velocity inferred from the early spectra of some Type II SNe. For explosions in even denser CSM, radiative acceleration can affect the dissipation of strong collisionless shocks formed after the shock breakout, which would affect early nonthermal emission expected from particle acceleration.

Keywords: Type II supernovae, Circumstellar matter, Hydrodynamics
Raman Scattering by Atomic Hydrogen in Photodissociation Regions: An Alternative to the Polycyclic Aromatic Hydrocarbons Hypothesis. Photodissociation regions (PDRs) illuminated by high temperature (T &gt; 104 K) radiation fields display characteristic optical to midinfrared spectral features: emission bands that cluster around the blue limits of hydrogen series, an extended red emission (ERE) in the vicinity of Hα, and a continuum in the infrared part of the spectrum only. The spectral footprint of ERE and its intensity at maximum unequivocally designate Raman scattering by hydrogen of photons near Lyβ as responsible for the feature, thus suggesting PDR spectra be considered Raman spectra. This finding challenges the currently accepted hypothesis that yet-to-be-identified complex carbonaceous molecules, such as polycyclic aromatic hydrocarbons, are the source of PDRs' unidentified infrared bands. It has, therefore, significant implications for the field of astrochemistry.

Keywords: Infrared excess, Interstellar emissions
Solar Wind Modeling with the Alfvén Wave Solar atmosphere Model Driven by HMI-based Near-real-time Maps by the National Solar Observatory. We explore the performance of the Alfvén Wave Solar atmosphere Model with near-real-time (NRT) synoptic maps of the photospheric vector magnetic field. These maps, produced by assimilating data from the Helioseismic Magnetic Imager (HMI) on board the Solar Dynamics Observatory, use a different method developed at the National Solar Observatory (NSO) to provide a near contemporaneous source of data to drive numerical models. Here, we apply these NSO-HMI-NRT maps to simulate three full Carrington rotations: 2107.69 (centered on the 2011 March 7 20:12 CME event), 2123.5 (centered on 2012 May 11), and 2219.12 (centered on the 2019 July 2 solar eclipse), which together cover various activity levels for solar cycle 24. We show the simulation results, which reproduce both extreme ultraviolet emission from the low corona while simultaneously matching in situ observations at 1 au as well as quantify the total unsigned open magnetic flux from these maps.

Keywords: Magnetohydrodynamical simulations, Magnetohydrodynamics, Solar wind, Magnetogram