Sazuna/UAT_keywords huggingface dataset:
An Inclusive Library for Quantitative Analysis of the Laser-induced Breakdown Spectra Acquired by the Zhurong Mars Rover. Laser-induced breakdown spectroscopy (LIBS) is a critical tool for geochemical analysis in planetary science due to its ability to remotely detect a broad range of elements at submillimeter spatial resolution. However, matrix effects and environmental complexities on Mars pose significant challenges to LIBS data calibration. ChemCam and SuperCam are the two LIBS instrument-bearing payloads previously mounted on NASA's Curiosity and Perseverance rovers, respectively. Dedicated LIBS spectral databases of ChemCam and SuperCam have facilitated a series of scientific research. In 2021, the Zhurong rover successfully landed on Mars and conducted investigations in Utopia Planitia, revealing evidence of prolonged water activity. Although the Mars Surface Composition Detector (MarSCoDe) placed on the rover contains a LIBS instrument, its contribution has been less prominent among the various payloads due to the absence of a dedicated LIBS spectral database to aid in data interpretation. In this study, we constructed a comprehensive LIBS spectral database tailored for the MarSCoDe, leveraging its engineering qualification model under simulated Martian conditions. The library incorporates 322 samples, including Martian soil simulants mixed with gradients of hydrous minerals, evaporated salts, and life-essential elements. Multivariate regression models were developed and validated, demonstrating high accuracy for quantitative analysis of major elements. Comparative analyses revealed the complementarity of this library to ChemCam and SuperCam datasets. This resource enhances the capability of MarSCoDe to interpret hydrous minerals and supports cross-instrument data integration, advancing our understanding of Martian aqueous history and potential habitability.

Keywords: Mars
Do Both Black Holes Spin in Merging Binaries? Evidence from GWTC-4 and Astrophysical Implications. Angular momentum transport in high-mass stars is commonly modeled by extrapolating the behavior of better-observed low-mass stars. According to the conventional picture, the cores of most black hole progenitors lose almost all of their angular momentum when their outer layers are ejected before core collapse. Accordingly, most black holes are expected to be born with dimensionless spin magnitudes of χ ≲ 0.01, even if some black holes are born with nonnegligible spin due to tidal interactions in a progenitor binary. One might therefore expect to find a large fraction of χ ≲ 0.01 black holes in merging binary black hole (BBH) systems. We find that the conventional picture of angular momentum transport is in tension with data from LIGO─Virgo─KAGRA's fourth Gravitational-wave Transient Catalog. We find no support for a subpopulation of BBH systems with χ ≲ 0.01. Neither do we find support for a subpopulation with only one spinning black hole as expected for tidal spin-up scenarios. Instead, we find evidence for two subpopulations in which both black holes have nonnegligible spin. Approximately 84% of BBH systems contain two black holes with modest spins χ ≍ 0.1 and approximately 16% contain two black holes with large spins χ ≍ 0.8. These estimates come from our best-fit model, which is favored with natural log Bayes factors  lnB≳3  over models that require a subpopulation of χ ≲ 0.01 black holes and models that do not contain multiple-spin subpopulations. These results are difficult to reconcile with our current understanding of angular momentum transport.

Keywords: Gravitational wave astronomy, Gravitational waves, Black holes, Compact objects
Thermoelastic Contraction as a Suppressor of Atmospheric Escape in Close-in Exoplanets. The survival of volatile-rich atmospheres on close-in exoplanets challenges classical escape models. We identify a fully classical, interior-driven correction: thermoelastic contraction of the planetary mantle slightly increases the gravitational binding energy and the effective escape threshold. Incorporating pressure and temperature-dependent elastic deformation, we define a dimensionless suppression index  Ξ≡(1−ϵV/3)−1/2  that links interior strain to escape dynamics. Across super-Earth and sub-Neptune regimes, realistic volumetric strains (ϵV ∼ 10−3─10−2) enhance the escape velocity by 0.02%─0.17%, yielding ≲1% reductions in energy-limited mass-loss rates. Critically, the Jeans regime amplifies this effect through its exponential sensitivity to vesc: for representative super-Earth parameters, thermoelastic contraction alone suppresses the Jeans escape rate by up to ∼18%. This establishes mantle elasticity as a small but physically robust correction to escape theory and a novel interior─atmosphere coupling channel. For instance, in the case of K2─18b, the predicted contraction-induced signal corresponds to ∼30 ppm at 1.4 μm, within the reach of JWST/NIRSpec in ∼5 transits. We outline observational tests—particularly with JWST and ARIEL—where high signal-to-noise transmission spectroscopy could, in favorable cases, probe these suppression signatures and place constraints on deep planetary structure.

Keywords: Exoplanet atmospheric dynamics, Exoplanet structure, Exoplanet atmospheric evolution, Exoplanet atmospheres, Exoplanet atmospheric structure
Resolved Profiles of Stellar Mass, Star Formation Rate, and Predicted CO-to-H<SUB>2</SUB> Conversion Factor Across Thousands of Local Galaxies. We present radial profiles of surface brightness in UV and IR bands, estimate stellar mass surface density (Σ⋆) and star formation rate surface density (ΣSFR), and predict the CO-to-H2 conversion factor (αCO) for over 5000 local galaxies with stellar mass M⋆ ≥ 109.3 M⊙. We build these profiles and measure galaxy half-light radii using GALEX and WISE images from the z0MGS program, with special care given to highly inclined galaxies. From the UV and IR surface brightness profiles, we estimate Σ⋆ and ΣSFR and use them to predict αCO with state-of-the-art empirical prescriptions. We validate our (kpc-scale) αCO predictions against observational estimates, finding the best agreement when accounting for CO-dark gas as well as CO emissivity and excitation effects. The CO-dark correction plays a primary role in lower-mass galaxies, whereas CO emissivity and excitation effects become more important in higher-mass and more actively star-forming galaxies, respectively. We compare our estimated αCO to observed galaxy-integrated SFR to CO luminosity ratio as a function of M⋆. A large compilation of literature data suggests that star-forming galaxies with M⋆ = 109.5─11 M⊙ show strong anticorrelations of SFR/ L'CO(1─0)∝M⋆−0.29  and SFR/ L'CO(2─1)∝M⋆−0.40 . The estimated αCO trends, when combined with a constant molecular gas depletion time tdep, can only explain ≍1/3 of these SFR/ L'CO  trends. This suggests that tdep being systematically shorter in lower-mass star-forming galaxies is the main cause of the observed SFR/ L'CO  variations. We publish all data products from this work, including galaxy sizes, UV and IR surface brightness profiles, Σ⋆, ΣSFR, and αCO estimates.

Keywords: Molecular gas, Star formation, Disk galaxies, CO line emission
Tracing the Physical Lineage of GRB 211211A: Population Constraints on NS─WD Merger Gamma-Ray Bursts. The peculiar long gamma-ray burst (GRB) event, GRB 211211A, is known for its association with a kilonova feature. Whereas most long GRBs are thought to originate in the core collapse of massive stars, the presence of a kilonova suggests GRB 211211A was instead produced by a merger of a compact object binary. Building on the interpretation put forward by J. Yang et al.—who argue that GRB 211211A was powered by a massive white dwarf─neutron star (WD─NS) merger—we adopt this WD─NS scenario as our observationally supported starting point. If the burst truly originates from that channel, its rarity must mirror the formation and merger rate of WD─NS binaries—a rate still largely unexplored in conventional massive-binary population studies. In this work, we present a qualitative analysis based on binary evolution physics in order to understand the fraction of GRB 211211A in short GRBs (NS─WD/NS─NS fraction). Since the progenitors of massive WD─NS binaries occupy the initial mass function-preferred regime, where the zero-age main sequence mass range of the assumed WD mass range (1.2─1.4 M⊙) is comparable to that of NSs, the NS─WD/NS─NS fraction emerging from our standard evolutionary path is expected to be ∼14%─37%, far higher than the observed fraction (∼5%). This discrepancy might imply a large, still-unidentified population of GRB 211211A-like events or an unusual origin of the NS—such as being hypernova-born or accretion-induced-collapse-born. Placing these results in a broader compact-binary context, implications for black-hole systems are also discussed.

Keywords: Stellar astronomy, Gamma-ray bursts, Binary stars, High energy astrophysics
The Stellar Morphology and Size of X-Ray-selected Active Galactic Nucleus Host Galaxies Revealed by JWST. We investigate the stellar shape and size─mass relationship of X-ray-selected active galactic nucleus (AGN) host galaxies using the high angular resolution and deep sensitivity in the near-infrared of the COSMOS-Web JWST survey field. We present the rest-frame 1 μm size, stellar mass, Sérsic index, axis ratio, and Gini─M20 parameters of 690 moderate-luminosity active galactic nuclei (AGNs) between redshift 0 and 3 and with stellar mass  logMs/M⊙∼10.75 . We find that AGN host galaxies have effective radii of 1─5 kpc, which is in between star-forming galaxies (SFGs) and quiescent galaxies (QGs) of the same stellar mass. AGN hosts have similar size─mass trends to SFGs and QGs, being smaller at higher redshift for the same stellar mass. The slope of the size─mass relationship of AGN host galaxies is steeper than that of SFGs. Their rest-frame 1 μm stellar morphology indicates a significant spheroidal component. We observed a low merger fraction (6%) in our sample, as well as substructures similar to disks, bars, and spiral arms in the residual images, which are in tension with evolutionary pathways that require major mergers. However, they may also be due to the different timescales between mergers and AGN activity.

Keywords: AGN host galaxies, Active galaxies
Constraints on the Progenitor and Explosion of SN 2024ggi in Harmony with Preexplosion Detection and Hydrodynamic Simulations. Supernova (SN) 2024ggi is a nearby Type II SN discovered by the Asteroid Terrestrial-impact Last Alert System, showing early flash-ionization features. The preexplosion images reveal a red supergiant progenitor with an initial mass of 10─17 M⊙. In the present work, we perform detailed hydrodynamic modeling to refine and put robust constraints on the progenitor and explosion parameters of SN 2024ggi. Among the progenitor models in our study, the pre-SN properties of the 11 M⊙ match the preexplosion-detected progenitor well. However, we find it difficult to completely rule out the 10 and 12 M⊙ models. Thus, we provide a constraint of 11 −1+1  M⊙ on the initial mass of the progenitor. To match the observed bolometric light curve and velocity evolution of SN 2024ggi, the favored model with an initial mass of 11 M⊙has a pre-SN radius of 800 R⊙. This model requires an explosion energy of [0.7─0.8] × 1051 erg, nickel mass of 0.049 M⊙, ejecta mass of 9.1 M⊙, and an amount of ∼ 0.5 M⊙ of steady-wind circumstellar medium (CSM) extended up to ∼1.2 × 1014 cm resulting from an eruptive mass-loss rate of 1.0 M⊙ yr−1. We also incorporate the accelerated-wind CSM scenario, which suggests a mass-loss rate of 1.0 × 10−2 M⊙ yr−1 and a CSM mass of ∼0.7 M⊙extended up to ∼1.1 × 1014 cm. This mass-loss rate falls within the range constrained observationally. Additionally, due to the constraint of 11 −1+1  M⊙ on the initial mass, the range of pre-SN radius and ejecta mass would be [690─900] R⊙ and [8.2─9.6] M⊙, respectively.

Keywords: Type II supernovae, Red supergiant stars, Stellar evolution
General Implicit Runge─Kutta Integrators for Multifluid Gas─Dust Aerodynamic Drag. The integration of aerodynamic drag is a fundamental step in simulating dust dynamics in hydrodynamical simulations. We propose a novel integration scheme, designed to be compatible with Strang splitting techniques, which allows for the straightforward integration of external forces and hydrodynamic fluxes in general-purpose hydrodynamic simulation codes. Moreover, this solver leverages an analytical solution to the problem of drag acceleration, ensuring linear complexity even in cases with multiple dust grain sizes, as opposed to the cubic scaling of methods that require a matrix inversion step. This new general implicit Runge─Kutta (GIRK) integrator is evaluated using standard benchmarks for dust dynamics such as DUSTYBOX, DUSTYWAVE, and DUSTYSHOCK. The results demonstrate not only the accuracy of the method but also the expected scalings in terms of accuracy, convergence to equilibrium, and execution time. GIRK can be easily implemented in hydrodynamical simulations alongside hydrodynamical steps and external forces and is especially useful in simulations with a large number of dust grain sizes.

Keywords: Astrophysical dust processes, Dust physics, Computational methods, Computational astronomy
Dynamical Environment and Stability around Centaur (2060) Chiron. A recent stellar occultation revealed that the Centaur (2060) Chiron hosts a broad disk extending beyond ∼200 km from its center, embedding three ring-like structures (Chi1R, Chi2R, and Chi3R), while a tenuous outer ring (Chi4R) lies beyond the Roche limit. Here, we present a first dynamical assessment of the system's stability through numerical simulations of test particles, accounting for Chiron's triaxial figure. For an equatorial ellipticity of C22 ∼ 0.02, as inferred from the most recent shape estimates, our simulations reveal a chaotic inner zone extending to ∼260 km, where particle lifetimes reach up to a year, while particles beyond ∼260 km can remain stable for at least a decade. These results suggest that the innermost portion of the disk is ephemeral and can only persist if continuously replenished. For lower ellipticity values (C22 ≲ 0.012), however, the entire disk is located within the stable region, regardless of Chiron's mass. Under the physical parameters currently available in the literature, Chi2R is possibly linked to the 1:3 spin-orbit resonance, while Chi1R cannot be linked to the 1:2 resonance, as previously proposed, since this resonance is unstable. Instead, Chi1R and Chi3R may be associated with the 2:5 and 1:5 spin─orbit resonances, respectively. Both the 1:3 and 1:5 resonances are bifurcated, generating chaotic zones that may explain the gap in Chi2R and the longitudinal asymmetry observed in Chi3R.

Keywords: Ring resonance, Centaur group, Planetary rings, Asteroids
Living with Neighbors. VI. Unraveling the Dual Impact of Bars on Star Formation in Paired Galaxies Using DESI. We present a comprehensive investigation into the influence of stellar bars on star formation (SF) in galaxy pairs, using a large sample of low-redshift galaxies (0.02 &lt; z &lt; 0.08) from the DESI Legacy Imaging Surveys Data Release 8. Our analysis examines whether bars enhance or suppress SF during pair interactions, and how these outcomes depend on the star-forming properties of companion galaxies. We find that bars either catalyze or inhibit SF in their host galaxies, depending on the companion's SF activity. In particular, barred galaxies paired with actively star-forming companions experience more pronounced central starbursts (with specific star formation rate up to ∼2.5 dex higher) than unbarred counterparts, whereas those with passive companions often have suppressed SF (sometimes below isolated galaxy levels). The notion of the dual role of bars can reconcile conventional conflicting reports of bar-driven enhancement versus quenching of SF activity. Bars, well known to regulate kiloparsec-scale dynamics, may also link to the impact of external environments: When a star-forming companion provides sufficient gas, bars drive central starbursts, whereas in gas-poor interactions, bars hasten gas depletion and contribute to SF suppression. This work highlights the necessity of accounting for both internal structure and companion properties to fully understand SF regulation in interacting galaxies.

Keywords: Galaxy bars, Disk galaxies, Galaxy interactions, Star formation, Galaxy evolution
Precision Mass Measurement of <SUP>26</SUP>P and <SUP>27</SUP>S and Their Impact on the <SUP>26</SUP>P(p,γ)<SUP>27</SUP>S Reaction in Stellar X-Ray Bursts. Based on the experimental Cooler Storage Ring in Lanzhou, we directly determined the masses of 27S and 26P using Bρ-defined isochronous mass spectrometry. The mass excesses were determined to be 17,437(24) keV for 27S and 10,997(10) keV for 26P. These values yield a proton separation energy of 849(26) keV for 27S, representing an eightfold precision improvement over the previous one of 581(214) keV. With precisely measured masses, we evaluated the thermonuclear 26P(p, γ)27S reaction rate under X-ray burst conditions. The updated rate is enhanced within the 0.4─2 GK temperature range, reaching up to 5 times the previous rate at 1 GK. The uncertainty of the reverse 27S(γ, p)26P reaction rate is drastically reduced with the new high-precision mass results, from over 10 orders of magnitude to less than one. We further assessed the impact of the revised rates on the nucleosynthesis in Type I X-ray bursts using a one-zone postprocessing model. The results show that the final abundance ratio of 27S to 26P is increased by about 1 order of magnitude, indicating a more efficient reaction flow toward 27S. Although the sequence 25Si(p, γ)26P(p, γ)27S(β+)27P is not on the main rp-process path, it emerges as a nonnegligible branch contributing to 27P synthesis.

Keywords: Mass spectrometers, Reaction rates, X-ray bursts, Nuclear physics
Where are the Population III Star Relics in the Simulated Milky Way Analogs?. Using six Milky Way analogs with two different numerical resolutions from the Auriga simulation, we investigate the total mass, spatial distribution, and kinematics of the Population III (Pop III) star relics in the Milky Way analogs at z = 0. These relics (primarily second-generation stars) formed over a wide redshift range, from about z = 22 to z = 4, with an average formation redshift of z ∼ 10.0, and comprise about 2 × 10−5 of the entire galactic stellar population. The disk and bulge components host only a small fraction of these relics, contributing less than 12% in total. The stellar halo, in particular the outer stellar halo of galactic radius r &gt; 30 kpc, hosts the largest fraction (about 46% on average), with an average of one relic star per 4000 to 10,000 stars, making it a promising region for observational searches. Additionally, around 18% of the Pop III star relics are found in satellite galaxies, with smaller and older satellite galaxies tending to contain a higher proportion of these stars. Thus, low-mass and early-formed satellite galaxies are also ideal targets for finding such relics, although some satellite galaxies may lack them entirely. The spatial distribution and kinematics of these stars show good numerical convergence across different simulation resolutions. Our results provide valuable guidance for searches of the Pop III star relics and offer insights for interpreting findings from ongoing and future stellar archaeology surveys.

Keywords: Population II stars, Galactic archaeology, Milky Way Galaxy, Hydrodynamical simulations
Fragmentation-limited Dust Filtration in 2D Simulations of Planet─Disk Systems with Dust Coagulation: Parameter Study and Implications for the Inner Disk's Dust Mass Budget and Composition. Superthermal gas giant planets or their progenitor cores are known to open deep gaps in protoplanetary disks, which stop large, drifting dust particles on their way to the inner disk. The possible separation of the disk into distinct reservoirs and the resulting dust depletion interior to the gap have important implications for planetesimal formation and the chemical and isotopic composition of the inner regions of protoplanetary disks. Dust fragmentation, however, maintains a reservoir of small grains that can traverse the gap. Dust evolution models are thus instrumental for studies of a gap's filtration efficiency. We present 2D multifluid hydrodynamic simulations of planet─disk systems with dust coagulation and fragmentation. For the first time, we evolve a series of 2D simulations with dust coagulation over 45,000 planetary orbits and track the dust's size evolution and origin by using the TriPoD dust coagulation method. We investigate the effects of different planetary masses, fragmentation velocities, and viscosities on the inner disk's dust mass budget and composition, and highlight the advantages of multidimensional simulations over 1D models. Filtering can only be efficient for high planetary masses, high fragmentation velocities, and low diffusivities. Clear compositional distinctions between the inner and outer disk could not have been maintained by Jupiter's core if the fragmentation velocity was low, even if α ≲ 5 × 10−4. Significant "contamination" of the inner disk by outer-disk dust occurs in much less than 2 × 105 yr in this case and even for more-massive objects. This either places tight constraints on the physical conditions in the solar nebula or mandates consideration of alternative explanations for the dichotomy between non-carbonaceous chondrites (NC) and carbonaceous chondrites (CC). Astrophysical constraints on the parameters could discriminate between these possibilities.

Keywords: Dust physics, Hydrodynamical simulations, Solar system formation, Dust composition, Protoplanetary disks, Planet formation
What Can We Learn about Reionization Astrophysical Parameters Using Gaussian Process Regression?. Reionization is one of the least understood processes in the evolution history of the Universe, mostly because of the numerous astrophysical processes occurring simultaneously about which we do not have a very clear idea so far. In this article, we use the Gaussian process regression (GPR) method to learn the reionization history and infer the astrophysical parameters. We reconstruct the UV luminosity density function using the Hubble Frontier Fields and early JWST data. From the reconstructed history of reionization, the global differential brightness temperature fluctuation during this epoch has been computed. We perform Markov Chain Monte Carlo (MCMC) analysis of the global 21 cm signal using the instrumental specifications of SARAS, in combination with Lyα ionization fraction data, Planck optical depth measurements, and UV luminosity data. Our analysis reveals that GPR can help infer the astrophysical parameters in a more model-agnostic way than conventional methods. Additionally, we analyze the 21 cm power spectrum using the reconstructed history of reionization and demonstrate how the future 21 cm mission Square Kilometre Array, in combination with Planck and Lyα forest data, improves the bounds on the reionization astrophysical parameters by doing a joint MCMC analysis for the astrophysical parameters plus six cosmological parameters for the ΛCDM model. The results make the GPR-based reconstruction technique a robust learning process, and the inferences on the astrophysical parameters obtained therefrom are quite reliable and can be used for future analysis.

Keywords: Cosmology, Luminosity function, Cosmic microwave background radiation, Gaussian Processes regression, Intergalactic medium, Markov chain Monte Carlo, Reionization