Sazuna/UAT_keywords huggingface dataset:
Dissecting the Multiple Component Outflow in NGC 5548 with Absorption Line Variability. Active galactic nucleus (AGN)-driven outflows are routinely invoked as a key agent of supermassive black holes to regulate the evolution of galaxies. The radial distance from the central engine is a crucial parameter for evaluating the impact of these outflows on the host galaxy. In this work, we estimate the radial distances of UV outflow components in NGC 5548 using the most up-to-date absorption line variability method, combined with multi-epoch Hubble Space Telescope (HST)/Cosmic Origins Spectrograph spectroscopy from the 2014 AGN STORM campaign and archival data observed in 2013. The recombination timescale (tr) of the absorbers is measured by analyzing the detection rate curves of absorption line variability. In particular, the detection rate curves of the absorption troughs showing blended multiple velocity components are featured by distinct "multistep" profiles, allowing for measuring tr for individual components. Among the six identified outflow components, four are found to be a few parsecs from the center, and two are 30─40 pc away. Our results agree well with the more reliable results in the literature on components 1 and 4, and show overall consistency with previous works, demonstrating the power of our new methodology, especially when it is aided by densely sampled HST spectra.

Keywords: Seyfert galaxies, Active galactic nuclei
Extremely Luminous Optical Afterglow of an Energetic Gamma-Ray Burst GRB 230204B. Robotic telescope networks play an important role in capturing early and bright optical afterglows, providing critical insights into the energetics and emission mechanisms of GRBs. In this study, we analyze GRB 230204B, an exceptionally energetic and multipulsed long GRB, detected by the Fermi Gamma-ray Burst Monitor and MAXI detectors, with an isotropic equivalent gamma-ray energy exceeding 1054 erg. Time-resolved spectral analysis reveals a transition in the prompt emission from hard (sub-photospheric-dominated) spectra during early pulses to softer (synchrotron-radiation-dominated) spectra in later pulses, indicative of a hybrid jet composition. We report the discovery and characterization of the optical afterglow using the Mobile Astronomical System of Telescope-Robots (MASTER) and Burst Observer and Optical Transient Exploring System (BOOTES) robotic telescope networks, which enabled rapid follow-up observations starting at ∼1.3 ks post-burst. The optical luminosity at this time was exceptionally high, surpassing that of many other optically bright GRBs, such as GRB 990123 and GRB 080319B. This places the burst among the most luminous optical GRBs observed to date. Long-term radio observations extending to 335 days post-burst were conducted with the Australia Telescope Compact Array. Multiwavelength modeling, incorporating data from MASTER, BOOTES, Devasthal Optical Telescope, Swift/XRT, and radio observations, was conducted using an external interstellar medium (ISM) forward-shock top-hat jet model with afterglowpy. The results reveal a narrow and highly collimated jet with a circumburst density of n0 ∼ 28.12 cm−3, kinetic energy EK ∼ 4.18 × 1055 erg, and a relatively low value of ϵB = 2.14 × 10−6, indicating shock-compression of the magnetic field in the surrounding ISM. We constrained a low radiative efficiency of ∼4.3%. This study highlights the indispensable contribution of robotic networks to early afterglow observations and advances our understanding of GRB 230204B unique characteristics and underlying jet physics.

Keywords: Gamma-ray bursts
Galactic Bars Are Already Mature at Cosmic Noon: Bar Strength and Flatness at z ∼ 1.5. In this work, we explore the nature of z &gt; 1 galactic bars. Once thought to be highly transient, our results demonstrate otherwise. Our sample consists of nine massive (&gt;1010.5 M⊙) star-forming barred-spiral galaxies at zspec ∼ 1.5. Using rest-frame near-IR (F444W) JWST/NIRCam imaging, we apply ellipse fitting along with 1D and 2D morphological modeling to directly measure bar properties. We find that five galaxies host flat surface brightness profiles (bar Sérsic index &lt; 0.4), indicative of highly evolved, "mature" bars. By contrast, only two galaxies show exponential profiles, characteristic of young bars, and these are also shorter in absolute length than the flat bars. We therefore conclude that a large fraction of bars at this epoch have already matured, thereby indicating the presence of well-settled disks required to facilitate bar formation and sustained evolution well before z ∼ 1.5. To assess the gravitational impact of the bars, we calculate the maximum transverse-to-radial force ratio (Qb). We find that the Qb values are comparable to, or weaker than, those of bars in the local Universe; seven of the nine bars show only a marginal increase in strength with maturity (from exponential to flat bars). Contrarily however, the remaining two bars are flat, but have the lowest Qb values in our sample. We hence propose that the mature bars at z ∼ 1.5 may experience phases of weakening due to rapid gas inflows and/or minor mergers. In conclusion, our work sheds light on the rapidly evolving nature of high-z bars and paves the way for larger statistical studies.

Keywords: Galaxy bars, Barred spiral galaxies, Galaxy evolution
A Method for Quantifying Paleoenvironmental Impacts on Lunar Recession and the Moon's Age. Geological evidence indicates that the Moon formed at least 4.46 billion years ago. Models of Earth─Moon evolution generally describe tidal friction as the primary driver of lunar recession—the gradual increase in the lunar orbital semimajor axis—and the corresponding lengthening of Earth's day. However, tidal dissipation within Earth's oceans is sensitive to climatic and tectonic boundary conditions, which introduce variability not fully captured in existing models. Here, we develop a probabilistic framework that quantifies lunar recession and its variations by incorporating the influence of climate dynamics, plate tectonics, and geological constraints on Earth's length-of-day evolution. Applied to the past 1 billion years, the analysis yields an additional, previously unrecognized long-term lunar recession of ∼0.84 mm yr−1, equivalent to an orbital expansion of ∼808 km. This signal is primarily associated with sea-level change acting on the surface of the Earth with evolving plate configurations, with a particularly strong expression during the Cenozoic Era. The revised recession history adds an uncertainty of ∼15 million years to the lunar age. These findings suggest that slightly lower tidal dissipation rates than those used in earlier models provide better agreement with geological constraints on lunar chronology.

Keywords: Tides, Celestial mechanics, Earth-moon system
A Common Synchrotron Origin for Prompt Gamma-Ray and Soft X-Ray Emission in Gamma-Ray Bursts: Evidence from Joint Spectral Analysis. The recent launches of the Einstein Probe and the Space Variable Objects Monitor mission have led to the detection of a growing number of long gamma-ray bursts (GRBs) with significant, early soft X-ray flux during their gamma-ray emission, prompting the question of whether their multiband prompt emission shares a common origin in region and mechanism. To address this, we utilize the 20-year Swift archival data, which provides a substantial sample of joint soft X-ray and gamma-ray observations, enabling a systematic joint spectral study. We resolve 110 temporal pulses from 46 GRBs and find that a single power-law model with a low-energy break or cutoff adequately describes the prompt spectra from 150 keV down to 0.5 keV. More than half of the sample pulses require a break around a few keV, with average spectral indices &lt;α1&gt; = −0.88 and &lt;α2&gt; = −1.46 consistent with synchrotron radiation in a marginally fast-cooling regime. The observed spectral evolution and the distribution of indices support a single-emission-region origin, where the varying spectral shapes are largely governed by the evolution of the synchrotron cooling frequency νc and the effect of finite emission width. The observed differences in the temporal behavior between X-ray and gamma-ray light curves can be naturally explained by this spectral evolution across the broad band.

Keywords: Gamma-ray bursts
Abundant Population of Broad Hα Emitters in the GOODS-N Field Revealed by CONGRESS, FRESCO, and JADES. We present a spectroscopic search for broad Hα emitters at z ≍ 3.7─6.5 in the GOODS-N field, utilizing JWST/NIRCam slitless spectroscopy from FRESCO and CONGRESS, complemented by JADES imaging. We identify 19 broad Hα emitters with FWHM &gt; 1000 km s−1 at z ≍ 4─5.5, including nine new sources. The broad Hα luminosity function derived from our sample is consistent with those of other JWST-selected broad-line active galactic nuclei (AGN) reported in the literature. The black hole masses and AGN bolometric luminosities inferred from the broad Hα components indicate that most sources are accreting at ∼10% of the Eddington limit. We derive their host stellar masses via spectral energy distribution (SED) fitting and find higher MBH/M* ratios relative to the local MBH─M* relations, consistent with previous studies. We find that 42% of the sample do not satisfy the widely used color selection criteria for little red dots (LRDs), with the majority of these sources lacking the characteristic steep rest-optical red slope, indicating that the LRD selection is highly incomplete when selecting AGN galaxies. A comparison of the average SEDs between our sample and LRDs selected in the same field reveals that the steep red slopes observed in some LRDs are likely due to line-boosting effects as previously suggested. Furthermore, we find that 68% of color-selected LRDs with Hα detections in the NIRCam/grism spectra do not exhibit broad-line features. While the limited sensitivity of the grism spectra may hinder the detection of broad-line components in faint sources, our findings still highlight the enigmatic nature of the LRD population.

Keywords: AGN host galaxies, Supermassive black holes, Active galactic nuclei, High-redshift galaxies
J-PAS and PFS Surveys in the Era of Dark Energy and Neutrino Mass Measurements. Fisher-matrix forecasts are presented for the cosmological surveys of the Javalambre Physics of the Accelerating Universe Astrophysical Survey (J-PAS) and the Subaru Prime Focus Spectrograph (PFS). The wide, low-redshift coverage of J-PAS and the high-density, high-redshift mapping of PFS are strongly complementary: combining the two reduces marginalized uncertainties on all primary parameters compared with either survey individually. Adding the joint J-PAS+PFS data to next-generation cosmic microwave background (CMB) measurements from the Simons Observatory and LiteBIRD yields an expected precision of σ(∑mν) = 0.017 eV in the ΛCDM+∑mν + Neff framework, sufficient to disfavor the inverted neutrino hierarchy at 2.34σ if the true mass sum equals the normal-ordering minimum. Motivated by recent DESI results, we also forecast within a w0waCDM+∑mν + Neff cosmology, adopting the DESI DR2 best-fit values (w0 = −0.758, wa = −0.82) as fiducial. The combination CMB+J-PAS+PFS then delivers σ(w0) = 0.044 and σ(wa) = 0.18, corresponding to a 5.1σ preference for a time-varying dark-energy equation of state. These findings show that J-PAS and PFS, especially when coupled with Stage IV CMB observations, will provide competitive tests of neutrino physics and the dynamics of cosmic acceleration.

Keywords: Cosmology, Neutrino masses, Cosmological parameters from large-scale structure
RUBIES Spectroscopically Confirms the High Number Density of Quiescent Galaxies from 2 &lt; z&lt; 5. We present the number density of massive ( log(M*/M⊙)&gt;10.3 ) quiescent galaxies at 2 &lt; z &lt; 5 using JWST NIRSpec PRISM spectra. This work relies on spectra from RUBIES, which provides excellent data quality and an unparalleled, well-defined targeting strategy to robustly infer physical properties and number densities. We identify quiescent galaxy candidates within RUBIES through principal component analysis and construct a final sample using star formation histories derived from spectrophotometric fitting of the NIRSpec PRISM spectra and NIRCam photometry. By inverting the RUBIES selection function, we correct for survey incompleteness and calculate the number density of massive quiescent galaxies at these redshifts, providing the most complete spectroscopic estimates prior to cosmic noon to date. We find that early massive quiescent galaxies are surprisingly common (≳10−5 Mpc−3 by 4 &lt; z &lt; 5), which is consistent with previous studies based on JWST photometry alone and/or in smaller survey areas. We compare our number densities with predictions from six state-of-the-art cosmological galaxy formation simulations. At z &gt; 3, most simulations fail to produce enough massive quiescent galaxies, suggesting the treatment of feedback and/or the channels for early efficient formation are incomplete in most galaxy evolution models.

Keywords: Extragalactic astronomy, High-redshift galaxies, Quenched galaxies, Galaxies
Evidence of 1:1 Slope between Rocky Super-Earths and Their Host Stars. The relationship between the composition of rocky exoplanets and their host stars is fundamental to understanding planetary formation and evolution. However, previous studies have been limited by inconsistent datasets, observational biases, and methodological differences. This study investigates the compositional relationship between rocky exoplanets and their host stars, utilizing a self-consistent and homogeneous dataset of 21 exoplanets and their 20 host stars. By applying sophisticated interior structure modeling and comprehensive chemical analysis, we identify a potential 1:1 best-fit line between the iron-mass fraction of planets and their host stars equivalent with a slope of  m=0.94−1.07+1.02  and intercept of  c=−0.02−0.29+0.31 . This results are consistent at the 1σ level with other homogeneous studies, but not with heterogeneous samples that suggest much steeper best-fit lines. Although our results remain tentative due to sample size and data uncertainties, the updated dataset significantly reduces the number of super-Mercuries from four to one, but it remains that several high-density planets are beyond what a primordial origin would suggest. The planets in our sample have a wider composition than that of stars, which could indicate formation pathways away from primordial or be the result of random scattering owing to current mass─radius uncertainties as we recover the observed outliers in mock population analysis ∼15% of the time. To truly determine whether the origin is primordial with a 1:1 true relation, we find that sample of at least 150 planets is needed and that stars that are iron enriched or depleted are high-value targets.

Keywords: Extrasolar rocky planets, Exoplanets, Stellar abundances, Super Earths, Exoplanet systems, Exoplanet astronomy, Planet hosting stars, Exoplanet structure, Exoplanet formation, Planetary interior, Planetary structure
H I Content of Group Galaxies from the FAST All Sky H I Survey. We investigate the atomic gas (H I) content of galaxies in groups using early data from the Five-hundred-meter Aperture Spherical Radio Telescope (FAST) All Sky H I survey. Taking advantage of FAST's blind, wide-area coverage and uniform sensitivity, we assemble a sample of 230 group galaxies belonging to 182 groups at z ≤ 0.03. These groups were identified using a halo-based group finder, and they have a median membership of four galaxies. We also derived a matched control sample of isolated systems, and apply censored-data modeling to include both detections and nondetections. At fixed stellar mass and color, we find that the global median H I fraction of group galaxies differs from that of controls by only −0.04 dex (95% CI [−0.18, 0.16]), indicating at most a mild average offset. The signal is not uniform across populations: satellites are H I poor (median ∆fH I = −0.12 dex), whereas centrals are not H I deficient (median ∆fH I = 0.13 dex). Group galaxies located within 0.5R180 and in denser systems (richness &gt; 10 or local density Σ &gt; 10 gal Mpc−2) show stronger negative offsets, whereas galaxies in the outskirts are statistically indistinguishable from the controls. These results refine earlier reports of global group H I deficiency: with deeper blind data and uniform treatment of upper limits, we show that H I depletion is primarily confined to satellites and compact cores rather than being ubiquitous across groups.

Keywords: Galaxy evolution, Galaxy groups, Interstellar atomic gas
Can Clump Properties Determine Core Distribution in Star Formation? A Statistical Analysis of Magnetohydrodynamic Simulations. Dense cores, the progenitors of stars, are in sub-pc scale and fragmented from pc-scale clumps. However, it is still unclear how strongly the fragmentation process is affected by the properties of the host clumps and how these properties influence the core distribution observed in recent millimeter (mm) and sub-mm observations. To systematically investigate this relation, we employed magnetohydrodynamic (MHD) simulations of convergent flows to generate a large sample of clumps and analyzed their properties using various techniques. Alignment parameters were used to quantify core distribution, while energy terms were calculated to assess the influence of gravity, magnetic fields, and turbulence. We found the core distribution only exhibiting weak correlations between alignment parameters and clump properties. For an individual clump, turbulence is believed to significantly contribute to these features by inducing nonhomologous collapse and ongoing fragmentation. Nevertheless, for the entire population, more compact core distributions are observed due to the dominance of gravity. Overall, these factors suggest that clump properties are not sufficient to accurately determine core distribution.

Keywords: Star forming regions, Star formation, Interstellar medium, Magnetohydrodynamical simulations
The Response of Rotating Stellar Convection to Latitudinally Varying Heat Flux. We investigate how rotating convection responds to the imposition of a latitudinally varying heat flux at the base of the convective layer. This study is motivated by the solar near-surface shear layer, whose flows are thought to transition from a buoyancy-dominated regime near the photosphere to a rotation-dominated regime at depth. Here, we conduct a suite of spherical 3D, nonlinear simulations of rotating convection that operate in either the buoyancy-dominated (high-Rossby-number, high-Ro) or rotation-dominated (low-Rossby-number, low-Ro) regime. At the base of each model convection zone, we impose a heat flux whose latitudinal variation is opposite to the variation that the system would ordinarily develop. In both the low- and high-Ro regimes, a strong thermal wind balance is sustained in the absence of forcing. With a larger flux variation, this balance becomes stronger at high latitudes and weaker at low latitudes. The resulting differential rotation weakens in response, and at sufficiently high forcing, its latitudinal variation reverses for both low- and high-Ro systems. At fixed forcing, there exists a Rossby number above which the convective flows efficiently mix heat laterally, and the imposed flux variation does not imprint to the surface. At sufficiently high Ro, thermal wind balance is no longer satisfied. We discuss these results within the context of the Sun's near-surface region, which possesses a weakened differential rotation when compared to the deep convection, along with little-to-no variation of photospheric emissivity in latitude.

Keywords: Stellar interiors, Stellar convective zones, Solar rotation, Solar differential rotation, Hydrodynamics, Solar interior, Helioseismology, Solar convective zone, Stellar rotation, Astrophysical fluid dynamics
High-order Gravity-mode Period Spacing Patterns of Intermediate-mass (1.5 M<SUB>⊙</SUB> &lt; M &lt; 3 M<SUB>⊙</SUB>) Main-sequence Stars. I. Perturbative Analysis. Theoretical study of the high-order gravity-mode period spacing (∆Pg) pattern is relevant to a better understanding of the internal properties of intermediate-mass (1.5 M⊙ &lt; M &lt; 8 M⊙) main-sequence g-mode pulsators. In this paper, we carry out first-order perturbative analysis to evaluate effects of a sharp, though not discontinuous, transition in the Brunt─Väisälä (BV) frequency on the ∆Pg pattern. Such a finite-width transition in the BV frequency, whose scale height can be comparable to the local wavelength of gravity waves, is expected to develop in relatively low-mass (1.5 M⊙ &lt; M &lt; 3 M⊙) main-sequence stars, causing a bump in the second derivative of the BV frequency. Inspired by Unno et al.'s formulation, we treat the bump in the second derivative of the BV frequency as a small perturbation, which allows us to derive an analytical expression for the ∆Pg pattern. The analytical expression shows that the amplitude of the oscillatory ∆Pg pattern is determined by a weighted average of the bump in the second derivative of the BV frequency, where the weighting function is given by the g-mode eigenfunction. Tests with low-mass (∼2 M⊙) main-sequence stellar models show that the analytical expression can reproduce the numerically computed ∆Pg patterns reasonably well. The results of our perturbative analysis will be useful, for example, in improving semi-analytical expressions for the ∆Pg pattern, thereby enabling investigations of ∆Pg patterns in slowly pulsating B-type stars and γ Dor stars to infer their chemical composition profiles and rotation rates.

Keywords: Stellar interiors, Stellar cores, Stellar oscillations, Asteroseismology, Stellar evolution
A Novel Reverberation Mapping Method for Blazars. Reverberation mapping (RM) is the most promising method to measure the masses of supermassive black holes in the center of active galactic nuclei. However, the dominant jet component hinders the application of the RM method for blazars. In this work, we present a new algorithm to disentangle the contribution of the accretion disk from that of the relativistic jet in blazars by analyzing the spectral break of the optical spectroscopic data. We applied this method to two flat-spectrum radio quasars, PKS 1510−089 and PKS 0736+017. In PKS 1510−089, the variability of the Hγ line is delayed with respect to the disk emission by approximately 94 days, while the Hβ line shows a lag of about 111 days relative to the disk. In PKS 0736+017, the Hγ variability is delayed with respect to the disk by roughly 66 days, and the Hβ line exhibits a lag of about 67 days. Based on these measured time lags, we estimate black hole masses of ∼1.4 × 108 M⊙ for PKS 1510−089 and ∼8.1 × 107 M⊙ for PKS 0736+017. This method paves the way to apply the RM method for blazars and improves the understanding of disk and jet activities.

Keywords: Blazars, Supermassive black holes, Active galactic nuclei