Sazuna/UAT_keywords huggingface dataset:
Ionized Carbon in Galaxies: The [C II] 158 μm Line as a Total Molecular Gas Mass Tracer Revisited. In this paper, we present a statistical study of the [C II] 158 μm line and the CO(1‑0) emission for a sample of ∼200 local and high-z (32 sources with z &gt; 1) galaxies with very different physical conditions. We explore the correlation between the luminosities of [C II] and CO(1‑0) lines and obtain a strong linear relationship, confirming that [C II] is able to trace total molecular gas mass, with a small difference between (U)LIRGs and less-luminous galaxies. The tight and linear relation between [C II] and CO(1‑0) is likely determined by the average value of the observed visual extinction A  V  and the range of G 0/n in galaxies. Further investigations into the dependence of L [C II]/L CO(1‑0) on different physical properties show that L [C II]/L CO(1‑0) (1) anticorrelates with ΣIR, and the correlation becomes steeper when ΣIR ≳ 1011 L ⊙ kpc‑2; (2) correlates positively with the distance from the main sequence Δ(MS) when Δ(MS) ≲ 0; and (3) tends to show a systematically smaller value in systems where the [C II] emission is dominated by ionized gas. Our results imply that caution needs to be taken when applying a constant [C II]-to-M mol conversion factor to estimate the molecular gas content in extreme cases, such as galaxies having low-level star formation activity or high star formation rate surface density.

Keywords: Starburst galaxies, Interstellar medium, Submillimeter astronomy, Ultraluminous infrared galaxies, High-redshift galaxies, Early-type galaxies
KIC 10855535: An Elegant δ Scuti Pulsator with Amplitude and Phase Modulation. We investigated the pulsating behavior of KIC 10855535 using Kepler 4 yr long-cadence data. Two independent frequencies were detected: a pulsation frequency F0 = 17.733260(5) day‑1 and a low frequency f 8 = 0.412643(8) day‑1. We identify F0 as the fundamental frequency, at which an equidistant quintuplet is centered, suggesting that the star orbits in a binary system. The fitted orbital parameters align well with those reported in previous literature. Long-term phase modulation caused by binarity has been confirmed by considering the light curve from the Transiting Exoplanet Survey Satellite. By removing the light-time effect, we measured a linear change in period of order  , a value that could be indicative of stellar evolution. The star also exhibits a gradual and stable amplitude growth, thereby raising the possibility of structural changes during its evolution. We attributed f 8 and its two harmonics to rotation and surface spots, with further analysis suggesting characteristics evolving over time. Based on this hypothesis, KIC 10855535 may rotate slowly for its type, with a speed of 37(2) km s‑1. Overall, KIC 10855535 presents an exceptionally clean spectrum and a relatively slow rotation as a δ Sct pulsator, exhibiting a single pulsation mode that undergoes both amplitude and phase modulation.

Keywords: Asteroseismology, Delta Scuti variable stars, Variable stars
Multiphase Gas Nature in the Sub-parsec Region of the Active Galactic Nuclei. III. Eddington Ratio Dependence on the Structures of Dusty and Dust-free Outflows. We investigated the influence of the Eddington ratio on sub-parsec-scale outflows in active galactic nuclei (AGNs) with supermassive black holes (SMBHs) masses of 107 M ⊙ using two-dimensional radiation hydrodynamics simulations. When the range of the Eddington ratio is γ Edd &gt; 10‑3, the radiation force exceeds the gas pressure, leading to stronger outflows and larger dust sublimation radius. Although the sub-parsec-scale outflows are a time-dependent phenomenon, our simulations demonstrated that the radial distributions can be well explained by the steady solutions of the spherically symmetric stellar winds. The dynamic structure of sub-parsec-scale outflows is influenced by the dust sublimation radius and the critical radii determined by the dynamical equilibrium condition. Although significantly affecting the outflow velocity, the Eddington ratio exerts minimal effects on temperature and number density distribution. Furthermore, our analytical solutions highlight the importance of the dust sublimation scale as a crucial determinant of terminal velocity and column density in dusty outflows. Through comparisons of our numerical model with the obscuring fraction observed in nearby AGNs, we reveal insights into the Eddington ratio dependence and the tendency toward the large obscuring fraction of the dusty and dust-free gases. The analytical solutions are expected to facilitate an understanding of the dynamical structure and radiation structures along the line of sight and their viewing angles from observations of ionized outflows.

Keywords: Hydrodynamical simulations, Active galactic nuclei, Astrophysicists, Hydrodynamics
zoomies: A Tool to Infer Stellar Age from Vertical Action in Gaia Data. Stellar age measurements are fundamental to understanding a wide range of astronomical processes, including Galactic dynamics, stellar evolution, and planetary system formation. However, extracting age information from main-sequence stars is complicated, with techniques often relying on age proxies in the absence of direct measurements. The Gaia data releases have enabled detailed studies of the dynamical properties of stars within the Milky Way, offering new opportunities to understand the relationship between stellar age and dynamics. In this study, we leverage high-precision astrometric data from Gaia DR3 to construct a stellar age prediction model based only on stellar dynamical properties, namely the vertical action. We calibrate two distinct, hierarchical stellar age–vertical action relations, first employing asteroseismic ages for red-giant-branch stars, then isochrone ages for main-sequence turn-off stars. We describe a framework called zoomies based on this calibration, by which we can infer ages for any star given its vertical action. This tool is open-source and intended for community use. We compare dynamical age estimates from zoomies with age measurements from open clusters and asteroseismology. We use zoomies to generate and compare dynamical age estimates for stars from the Kepler, K2, and TESS exoplanet transit surveys. While dynamical age relations are associated with large uncertainty, they are generally mass independent and depend on homogeneously measured astrometric data. These age predictions are uniquely useful for large-scale demographic investigations, especially in disentangling the relationship between planet occurrence, metallicity, and age for low-mass stars.

Keywords: Stellar kinematics, Milky Way dynamics, Stellar ages, Exoplanets
Searching for Radio Late-type Dwarf Stars in the GLEAM-X DR1 Catalog. We have developed a new method of multiwavelength data combination for the search of late-type radio dwarfs, and have put it into practice using GLEAM-X DR1 data. The initial sample is selected by cross-matching the Gaia/DR3 objects with the probability of being a star no less than 99%, and removing the extragalactic objects assigned by the SIMBAD database. The late-type dwarf stars are judged according to their location in the (BP ‑ RP)0/M G color–magnitude diagram and in the (J ‑ H)0/(K ‑ W1)0 near-infrared color–color diagram. Furthermore, stellar activity is searched by ultraviolet excess in the GALEX/NUV band and the Rossby number in the TESS light curves. In total, 12 stars are found to be late-type dwarf stars associated with radio source, which consists of five stars with UV excess and seven stars with a Rossby number less than 0.13. Three of these 12 stars are previously studied to be associated with radio objects. All these 12 stars are considered to be reliable counterparts of radio sources.

Keywords: Late-type dwarf stars, Radio astronomy, Stellar flares, Radio transient sources
MAGAZ3NE: Massive, Extremely Dusty Galaxies at z ∼ 2 Lead to Photometric Overestimation of Number Densities of the Most Massive Galaxies at 3 &lt; z &lt; 4. We present rest-frame optical spectra from Keck/MOSFIRE and Keck/NIRES of 16 candidate ultramassive galaxies targeted as part of the Massive Ancient Galaxies at z &gt; 3 Near-Infrared Survey (MAGAZ3NE). These candidates were selected to have photometric redshifts 3 ≲ z phot &lt;4, photometric stellar masses   &gt; 11.7, and well-sampled photometric spectral energy distributions (SEDs) from the UltraVISTA and VIDEO surveys. In contrast to previous spectroscopic observations of blue star-forming and poststarburst ultramassive galaxies, candidates in this sample have very red SEDs implying significant dust attenuation, old stellar ages, and/or active galactic nuclei (AGN). Of these galaxies, eight are revealed to be heavily dust-obscured 2.0 &lt; z &lt; 2.7 galaxies with strong emission lines, some showing broad features indicative of AGN, three are Type I AGN hosts at z &gt; 3, one is a z ∼ 1.2 dusty galaxy, and four galaxies do not have a confirmed spectroscopic redshift. In fact, none of the sample has ∣z spec ‑ z phot∣ &lt; 0.5, suggesting difficulties for photometric redshift programs in fitting similarly red SEDs. The prevalence of these red interloper galaxies suggests that the number densities of high-mass galaxies are overestimated at z ≳ 3 in large photometric surveys, helping to resolve the "impossibly early galaxy problem" and leading to much better agreement with cosmological galaxy simulations. A more complete spectroscopic survey of ultramassive galaxies is required to pin down the uncertainties on their number densities in the early Universe. ∗ The spectra presented herein were obtained at the W. M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California, and the National Aeronautics and Space Administration. The Observatory was made possible by the generous financial support of the W. M. Keck Foundation.

Keywords: High-redshift galaxies, Galaxy evolution
Signature of Vertical Mixing in Hydrogen-dominated Exoplanet Atmospheres. Vertical mixing is a crucial disequilibrium process in exoplanet atmospheres, significantly impacting chemical abundance and observed spectra. While current state-of-the-art observations have detected its signatures, the effect of vertical mixing on atmospheric spectra varies widely based on planetary parameters. In this study, we explore the influence of disequilibrium chemistry across a parameter space that includes eddy diffusion, surface gravity, internal and equilibrium temperature, and metallicity. We also assess the effectiveness of retrieval models in constraining the eddy diffusion coefficient. By running numerous 1D chemical kinetics models, we investigate the impact of vertical mixing on the transmission spectrum. We also built a custom fast-forward disequilibrium model, which includes vertical mixing using the quenching approximation and calculates the model abundance orders of magnitude faster than the chemical kinetics model. We coupled this forward model with an open-source atmospheric retrieval code, used it on the JWST simulated output data of our chemical kinetics model, and retrieved eddy diffusion coefficient, internal temperature, and atmospheric metallicity. We find that there is a narrow region in the parameter space in which vertical mixing has a large effect on the atmospheric transmission spectrum. In this region of the parameter space, the retrieval model can put high constraints on the transport strength and provide optimal exoplanets to study vertical mixing. In addition, the NH3 abundance can be used to constrain the internal temperature for equilibrium temperature T equi &gt; 1400 K.

Keywords: Atmospheric composition, Atmospheric dynamics, Exoplanet atmospheres
Volatile Element Depletion of Carbonaceous Chondrites—Insights from Mass-dependent Zinc, Cadmium, and Tellurium Isotope Variations. The origin of volatile depletion in the solar system remains a topic of intense debate. To further inform our understanding of the mechanisms involved, this study characterized the mass-dependent Zn, Cd, and Te isotope compositions and concentrations of a comprehensive suite of carbonaceous chondrites (CCs). In accord with previous studies, Zn and Te display covariations between light isotope enrichments and elemental depletions. Observed here for the first time, Cd shows a similar trend. These correlations are consistent with the interpretation that the primary volatile element budgets of CCs were established by mixing of a volatile-rich CI-like matrix and a volatile-depleted non-matrix endmember (NME) in the solar nebula. All three elements display minor isotopic variations in CI and CM chondrites, as a consequence of aqueous alteration at low temperatures. In contrast, Cd and Te isotope compositions and concentrations are highly variable in CV and CO (Cd) and CK chondrites (Te). This reflects mobilization of the elements during thermal metamorphism at distinct redox conditions. The data of this study show that the NME has Zn, Cd, and Te concentrations that are depleted to an identical level of 0.12 ± 0.03 × CI chondrites, and it is characterized by mass-dependent isotope compositions for all three elements that are fractionated to light isotope values relative to CIs by a similar extent. In conjunction with literature data, this suggests that the concentrations and isotope compositions of NME volatiles record the same depletion processes, and that the NME volatile inventory is likely hosted predominantly in chondrules.

Keywords: Isotope shifts, Carbonaceous chondrites, Mass spectrometry, Meteorite composition
Viscous Transonic Accretion Flows in Kerr Black Hole Geometry. We study viscous transonic accretion flows in vertical equilibrium in Kerr geometry. We employ the pseudo-Kerr formalism that accurately describes transonic flows around Kerr black holes and is applicable for modeling observational data. We study the effects of viscosity on the nature of sonic points and the parameter space that allows an accretion flow to possess multiple sonic points. We concentrate on the accretion solutions that can have centrifugal pressure supported shock waves and find that the shocks are weaker and are located farther from the black hole as the viscosity is enhanced. Moreover, if the viscosity is greater than a critical value, shocks do not form and the accretion flow can pass only through the inner sonic point close to the black hole and remains subsonic and Keplerian throughout the accretion disk. Since the resonance oscillation frequencies of the shock waves provide a measure of the observed quasiperiodic oscillation (QPO) frequencies, and since the location of shock waves depend on the spin of a black hole, it is clear that the QPO frequencies must depend on the spin of black hole as well. Our pseudo-Kerr approach makes it easier to compute spectra from an accretion flow with viscous dissipation and radiative cooling around a spinning black hole.

Keywords: Gravitation, Black hole physics, Accretion, Relativity
Search for High-excitation Emission Lines from a Quasar-scale Active Nucleus in Arp 220. The late-stage galaxy merger and prototypical ultraluminous infrared galaxy (ULIRG) Arp 220 is probed using the JWST Mid Infrared Instrument medium-resolution spectrometer to search for multiple diagnostic active galactic nuclei (AGN) emission lines in the low-interstellar-opacity spectral ranges of 5.3–7.9 μm and 12.9–16.0 μm. We detect none of the characteristic high-excitation AGN emission lines. The most diagnostic nondetections are of the [Ne VI] λ 7.652 μm and [Ne V] λ 14.32 μm lines, for which the combined upper limit is ∼10–20 times fainter than the equivalent limit from Spitzer data. We also use X-ray measurements of the reflected Fe Kα line to suggest a relatively low X-ray luminosity. These results suggest that the high obscuration observed along the line of sight to the nuclei of Arp 220 is isotropic and keeps any high-excitation emission from a putative AGN from escaping. An implication is that the observed mid-infrared output of the nuclei is essentially their bolometric luminosity, i.e., no significant additional energy escapes. We utilize this result to show that any embedded AGNs are accreting at no more than ∼5% of the Eddington rate, lower than many theoretical predictions for this stage of ULIRG evolution.

Keywords: AGN host galaxies, James Webb Space Telescope, Active galactic nuclei
PMN J1310–5552: A Gamma-Ray-emitting Blazar Candidate Harboring a Cosmic Monster. Relativistic jets manifest some of the most intriguing activities in the nuclear regions of active galaxies. Identifying the most powerful relativistic jets permits us to probe the most luminous accretion systems and, in turn, the most massive black holes. This paper reports the identification of one such object, PMN J1310‑5552 (z = 1.56), a blazar candidate of uncertain type detected with the Fermi Large Area Telescope (LAT) and Swift Burst Alert Telescope. The detection of broad emission lines in its optical spectra taken with the X-Shooter and Goodman spectrographs classifies it to be a flat-spectrum radio quasar. The analysis of the Goodman optical spectrum has revealed PMN J1310‑5552 harbors a massive black hole (log scale M BH = 9.90 ± 0.07, in M ⊙) and luminous accretion disk (log scale L disk = 46.86 ± 0.03, in erg s‑1). The fitting of the observed big blue bump with the standard accretion disk model resulted in the log scale M BH   (in M ⊙) and L disk   (in erg s‑1), respectively. These parameters suggest PMN J1310‑5552 hosts one of the most massive black holes and the most luminous accretion disks among the blazar population. The physical properties of this enigmatic blazar were studied by modeling the broadband spectral energy distribution considering the data from NuSTAR, Swift, Fermi-LAT, and archival observations. Overall, PMN J1310‑5552 is a powerful "MeV" blazar with physical parameters similar to other members of this unique class of blazars. These results provide glimpses of monsters lurking among the unknown high-energy emitters and demonstrate the importance of ongoing wide-field sky surveys to discover them.

Keywords: Gamma-ray astronomy, Blazars, Relativistic jets, Flat-spectrum radio quasars
On the Influence of the Solar Wind on the Propagation of Earth-impacting Coronal Mass Ejections. Coronal mass ejections (CMEs) are subject to changes in their direction of propagation, tilt, and other properties as they interact with the variable solar wind. We investigated the heliospheric propagation of 15 Earth-impacting CMEs observed during 2010 April to 2018 August in the field of view (FOV) of the Heliospheric Imager (HI) on board the STEREO. About half of the 15 events followed self-similar expansion up to 40 R ⊙. The remaining events showed deflection either in latitude, longitude, or a tilt change. Only 2 events showed significant rotation in the HI1 FOV. We also use toroidal and cylindrical flux rope fitting on the in situ observations of interplanetary magnetic field and solar wind parameters to estimate the tilt at L1 for these 2 events. Although the sample size is small, this study suggests that CME rotation is not very common in the heliosphere. We attributed the observed deflections and rotations of CMEs to a combination of factors, including their interaction with the ambient solar wind and the influence of the ambient magnetic field. These findings contribute to our understanding of the complex dynamics involved in CME propagation and highlight the need for comprehensive modeling and observational studies to improve space weather prediction. In particular, HI observations help us to connect observations near the Sun and near the Earth, improving our understanding of how CMEs move through the heliosphere.

Keywords: Solar storm, Solar wind, Solar coronal mass ejections, Heliosphere
Revealing the Quiescent Galaxy Population in the Spiderweb Protocluster at z = 2.16 with Deep HST/WFC3 Slitless Spectroscopy. We report the Hubble Space Telescope Wide Field Camera 3 G141 grism slitless spectroscopy observation of the core region of the Spiderweb protocluster at z = 2.16. We analyzed the spectra of all objects in a   field of view and identified 40 protocluster members, recovering 19 previously identified Hα emitters in addition to revealing 21 new members. The spectra allowed us to identify 11 galaxies with quiescent spectra. In all, 3 galaxies with quiescent spectra are possibly still star forming according to spectral energy distribution fitting, indicating a possible leftover or dust-obscured star formation. We estimate a quiescent fraction of ∼50% for M ⋆ &gt; 1011 M ⊙. About half of the quiescent galaxies possibly host an active galactic nucleus (AGN), hinting at AGN's key role in quenching galaxies in the protocluster environment. These quiescent galaxies have relatively more compact and concentrated light profiles than the star-forming members, but they are not yet as bulge dominated as local ellipticals. These results are consistent with previous studies that indicate the Spiderweb protocluster is in the maturing stage, with a red sequence that has begun forming.

Keywords: Galaxy evolution, Protoclusters, Quenched galaxies, High-redshift galaxy clusters
Dark Matter Halos of Luminous Active Galactic Nuclei from Galaxy–Galaxy Lensing with the HSC Subaru Strategic Program. We assess the dark matter halo masses of luminous active galactic nuclei (AGNs) over the redshift range 0.2–1.2 using galaxy–galaxy lensing based on imaging data from the Hyper Suprime-Cam Subaru Strategic Program (HSC-SSP). We measure the weak lensing signal of a sample of 48,907 AGNs constructed using HSC and Wide-field Infrared Survey Explorer photometry. As expected, we find that the lensing mass profile of total AGN sample is consistent with that of massive galaxies ( 10.61). Surprisingly, the lensing signal remains unchanged when the AGN sample is split into four host galaxy stellar mass bins. Specifically, we find that the excess surface density of AGNs residing in galaxies with high stellar masses significantly differs from that of the control sample. We further fit a halo occupation distribution model to the data to infer the posterior distribution of parameters including the average halo mass. We find that the characteristic halo mass of the full AGN population lies near the knee ( ) of the stellar-to-halo mass relation (SHMR). Illustrative of the results given above, the halo masses of AGNs residing in host galaxies with high stellar masses (i.e., above the knee of the SHMR) fall below the calibrated SHMR while the halo masses of the low stellar mass sample are more consistent with the established SHMR. These results indicate that massive halos with a higher clustering bias tend to suppress AGN activity, probably due to the lack of available gas.

Keywords: Weak gravitational lensing, Active galaxies