Sazuna/UAT_keywords huggingface dataset:
The Quest for the Missing Dust. I. Restoring Large-scale Emission in Herschel Maps of Local Group Galaxies. Because the galaxies of the Local Group have such large angular sizes, much of their diffuse, large-angular-scale emission is filtered out by the Herschel data reduction process. In this work, we restore this previously missed dust in Herschel observations of the Large Magellanic Cloud, Small Magellanic Cloud, M31, and M33. We do this by combining Herschel data (including new reductions for the Magellanic Clouds), in Fourier space, with lower-resolution data from all-sky surveys (Planck, IRAS, and COBE) that did not miss the extended emission. With these new maps, we find that a significant amount of emission was missing from uncorrected Herschel data of these galaxies: over 20% in some bands. Our new photometry also resolves the disagreement between fluxes reported from older HERITAGE Magellanic Cloud Herschel reductions and fluxes reported from other telescopes. More emission is restored in shorter-wavelength bands, especially in the galaxies' peripheries, making these regions 20%-40% bluer than before. We also find that the Herschel-PACS instrument response conflicts with the all-sky data, over the 20'-90' angular scales to which they are both sensitive, by up to 31%. By binning our new data based on hydrogen column density, we are able to detect emission from dust at low interstellar medium densities (at ΣH &lt; 1 M⊙ pc-2 in some cases), and are able to detect emission at much lower densities (a factor of 2.2 lower on average, and more than a factor of 7 lower in several cases) than was possible with uncorrected data.

Keywords: Interstellar dust, Local Group, Dwarf galaxies, Far infrared astronomy, Submillimeter astronomy, Astronomy data reduction
A Local Baseline of the Black Hole Mass Scaling Relations for Active Galaxies. IV. Correlations Between M<SUB>BH</SUB> and Host Galaxy σ, Stellar Mass, and Luminosity. The tight correlations between the mass of supermassive black holes (MBH) and their host-galaxy properties have been of great interest to the astrophysical community, but a clear understanding of their origin and fundamental drivers still eludes us. The local relations for active galaxies are interesting in their own right and form the foundation for any evolutionary study over cosmic time. We present Hubble Space Telescope optical imaging of a sample of 66 local active galactic nuclei (AGNs); for 14 objects, we also obtained Gemini near-infrared images. We use state-of-the-art methods to perform surface photometry of the AGN host galaxies, decomposing them into spheroid, disk, and bar (when present), and inferring the luminosity and stellar mass of the components. We combine this information with spatially resolved kinematics obtained at the Keck Telescopes to study the correlations between MBH (determined from single-epoch virial estimators) and host galaxy properties. The correlations are uniformly tight for our AGN sample, with intrinsic scatter 0.2-0.4 dex, smaller than or equal to that of quiescent galaxies. We find no difference between pseudo and classical bulges or barred and nonbarred galaxies. We show that all the tight correlations can be simultaneously satisfied by AGN hosts in the 107-109 M☉ regime, with data of sufficient quality. The MBH-σ relation is also in agreement with that of AGN with MBH obtained from reverberation mapping, providing an indirect validation of single-epoch virial estimators of MBH.

Keywords: AGN host galaxies, Supermassive black holes, Black hole physics, Scaling relations, Seyfert galaxies, Active galactic nuclei, Galaxy evolution
Oscillation Mode Variability in Evolved Compact Pulsators from Kepler Photometry. II. Comparison of Modulation Patterns between Raw and Corrected Flux. We present the second results of an ensemble and systematic survey of oscillation mode variability in compact pulsators observed with the original Kepler mission. Two types of flux calibrations, raw and corrected, collected on two hot B subdwarf stars, KIC 2438324 and KIC 11179657, are thoroughly examined with the goal of evaluating the difference in patterns when oscillation modes modulate in amplitude (AM) and frequency (FM). We concentrate on AMs and FMs occurring in seven multiplet components in each star as representative frequencies. The analysis shows that FM measurements are independent of the flux calibration we choose. However, if flux contamination by nearby stars is large, AMs may be significantly different between raw and corrected flux. In addition, AMs suffer, to some extent, from a systematic modulation pattern, which is most likely induced by instrumental effects and differs from one star to another. Our results indicate that stars with no contamination are better candidates to quantitatively compare modulation patterns with theory and should be given a higher priority for such studies, since light contamination will destroy real AM patterns.

Keywords: B subdwarf stars, Pulsation frequency method, Pulsation modes, Photometry, Stellar oscillations
Hyper Suprime-Cam Subaru Strategic Program: A Mass-dependent Slope of the Galaxy Size-Mass Relation at z &lt; 1. We present the galaxy size-mass (Re-M*) distributions using a stellar mass complete sample of ~1.5 million galaxies, covering ~100 deg2, with $\mathrm{log}({M}_{* }/{M}_{\odot })\gt 10.2\,(9.2)$ over the redshift range 0.2 &lt; z &lt; 1.0 (z &lt; 0.6) from the second public data release of the Hyper Suprime-Cam Subaru Strategic Program. We confirm that, at fixed redshift and stellar mass over the range of $\mathrm{log}({M}_{* }/{M}_{\odot })\lt 11$ , star-forming galaxies are on average larger than quiescent galaxies. The large sample of galaxies with accurate size measurements, thanks to the excellent imaging quality, also enables us to demonstrate that the Re-M* relations of both populations have a form of a broken power law, with a clear change of slopes at a pivot stellar mass Mp. For quiescent galaxies, below an (evolving) pivot mass of $\mathrm{log}({M}_{p}/{M}_{\odot })=10.2\mbox{--}10.6$ , the relation follows ${R}_{e}\propto {M}_{\ast }^{0.1}$ ; above Mp the relation is steeper and follows ${R}_{e}\propto {M}_{* }^{0.6\mbox{--}0.7}$ . For star-forming galaxies, below $\mathrm{log}({M}_{p}/{M}_{\odot })\sim 10.7$ the relation follows ${R}_{e}\propto {M}_{* }^{0.2}$ ; above Mp the relation evolves with redshift and follows ${R}_{e}\propto {M}_{* }^{0.3\mbox{--}0.6}$ . The shallow power-law slope for quiescent galaxies below Mp indicates that large low-mass quiescent galaxies have sizes similar to those of their counterpart star-forming galaxies. We take this as evidence that large low-mass quiescent galaxies have been recently quenched (presumably through environment-specific processes) without significant structural transformation. Interestingly, the pivot stellar mass of the Re-M* relations for both populations also coincides with the mass at which half of the galaxy population is quiescent, implying that the pivot mass represents the transition of galaxy growth from being dominated by in situ star formation to being dominated by (dry) mergers.

Keywords: Galaxy evolution
Measurements of Photospheric and Chromospheric Magnetic Field Structures Associated with Chromospheric Heating over a Solar Plage Region. In order to investigate the relation between magnetic structures and the signatures of heating in plage regions, we observed a plage region with the He I 1083.0 nm and Si I 1082.7 nm lines on 2018 October 3 using the integral field unit mode of the GREGOR Infrared Spectrograph (GRIS) installed at the GREGOR telescope. During the GRIS observation, the Interface Region Imaging Spectrograph obtained spectra of the ultraviolet Mg II doublet emitted from the same region. In the periphery of the plage region, within the limited field of view seen by GRIS, we find that the Mg II radiative flux increases with the magnetic field in the chromosphere with a factor of proportionality of 2.38 × 104 erg cm-2 s-1 G-1. The positive correlation implies that magnetic flux tubes can be heated by Alfvén wave turbulence or by collisions between ions and neutral atoms relating to Alfvén waves. Within the plage region itself, the radiative flux was large between patches of strong magnetic field strength in the photosphere or at the edges of magnetic patches. On the other hand, we do not find any significant spatial correlation between the enhanced radiative flux and the chromospheric magnetic field strength or the electric current. In addition to the Alfvén wave turbulence or collisions between ions and neutral atoms relating to Alfvén waves, other heating mechanisms related to magnetic field perturbations produced by interactions of magnetic flux tubes could be at work in the plage chromosphere.

Keywords: Solar ultraviolet emission, Solar chromospheric heating, Spectropolarimetry, Solar magnetic fields
The Evolving Interstellar Medium of Star-forming Galaxies, as Traced by Stardust. We analyze the far-infrared (FIR) properties of ~5000 star-forming galaxies at z &lt; 4.5, drawn from the deepest, super-deblended catalogs in the GOODS-N and COSMOS fields. We develop a novel panchromatic spectral energy distribution fitting algorithm, Stardust, that models the emission from stars, active galactic nuclei (AGNs), and infrared dust emission, without relying on energy balance assumptions. Our code provides robust estimates of the UV-optical and FIR physical parameters, such as the stellar mass (M*), dust mass (Mdust), infrared luminosities (LIR) arising from AGN and star formation activity, and the average intensity of the interstellar radiation field (⟨U⟩). Through a set of simulations we quantify the completeness of our data in terms of Mdust, LIR, and ⟨U⟩ and subsequently characterize the distribution and evolution of these parameters with redshift. We focus on the dust-to-stellar mass ratio (fdust), which we parameterize as a function of cosmic age, stellar mass, and specific star formation rate. The fdust is found to increase by a factor of 10 from z = 0 to z = 2 and appears to remain flat at higher z, mirroring the evolution of the gas fraction. We also find a growing fraction of warm to cold dust with increasing distance from the main sequence, indicative of more intense interstellar radiation fields, higher star formation efficiencies, and more compact star-forming regions for starburst galaxies. Finally, we construct the dust mass functions (DMFs) of star-forming galaxies up to z = 1 by transforming the stellar mass function to DMF through the scaling relations derived here. The evolution of fdust and the recovered DMFs are in good agreement with the theoretical predictions of the Horizon-AGN and IllustrisTNG simulations. * https://github.com/VasilyKokorev/stardust/

Keywords: Starburst galaxies, Astronomy software, Active galaxies, Infrared astronomy, Submillimeter astronomy, High-redshift galaxies, Galaxies
Establishing α Oph as a Prototype Rotator: Precision Orbit with New Keck, CHARA, and RV Observations. Alpha Ophiuchi (Rasalhague) is a nearby rapidly rotating A5IV star that has been imaged by infrared interferometry. α Oph is also part of a known binary system, with a companion semimajor axis of ~430 mas and a high eccentricity of 0.92. The binary companion provides the unique opportunity to measure the dynamical mass to compare with the results of rapid rotator evolution models. The lack of data near periastron passage limited the precision of mass measurements in previous work. We add new interferometric data from the MIRC combiner at the CHARA Array as well as new Keck adaptive optics imaging data with NIRC2, including epochs taken near periastron passage. We also obtained new radial velocities of both components at Fairborn Observatory. Our updated combined orbit for the system drastically reduces the errors of the orbital elements and allows for precise measurement of the primary star mass at the few percent level. Our resulting primary star mass of 2.20 ± 0.06 M⊙ agrees well with predictions from imaging results and matches evolution models with rotation when plotting on a Hertzsprung-Russell diagram. However, to truly distinguish between nonrotating and rotating evolution models for this system, we need ~1% errors on mass, which might be achieved once the distance is known to higher precision in future Gaia releases. We find that the secondary mass of 0.824 ± 0.023 M⊙ is slightly underluminous when compared to stellar evolution models. We show that α Oph is a useful reference source for programs that need ±1 mas astrometry.

Keywords: Binary stars, Stellar properties, Radial velocity, Spectroscopic binary stars, Visual binary stars, Interferometric binary stars, Stellar rotation
Gaia GraL: Gaia DR2 Gravitational Lens Systems. VI. Spectroscopic Confirmation and Modeling of Quadruply Imaged Lensed Quasars. Combining the exquisite angular resolution of Gaia with optical light curves and WISE photometry, the Gaia Gravitational Lenses group (GraL) uses machine-learning techniques to identify candidate strongly lensed quasars, and has confirmed over two dozen new strongly lensed quasars from the Gaia Data Release 2. This paper reports on the 12 quadruply imaged quasars identified by this effort to date, which is a ~20% increase in the total number of confirmed quadruply imaged quasars. We discuss the candidate selection, spectroscopic follow-up, and lens modeling. We also report our spectroscopic failures as an aid for future investigations.

Keywords: Strong gravitational lensing, Quasars
Self-modulation of Cosmic Rays in Molecular Clouds: Imprints in the Radio Observations. We analyze properties of nonthermal radio emission from the Central Molecular Zone (CMZ) and from individual molecular clouds, and argue that the observed features can be interpreted in the framework of our recent theory of self-modulation of cosmic rays (CRs) penetrating dense molecular regions. For clouds with gas column densities of ~1023 cm-2, the theory predicts depletion of sub-GeV CR electrons, occurring due to self-modulation of CR protons and leading to harder synchrotron spectra in the sub-GHz range. The predicted imprints of electron depletion in the synchrotron spectra agree well with the spectral hardening seen in available radio observations of the CMZ. A similar, but even stronger, effect on the synchrotron emission is predicted for individual (denser) CMZ clouds, such as the Sgr B2. However, the emission at frequencies above ~GHz, where observational data are available, is completely dominated by the thermal component, and therefore new observations at lower frequencies are needed to verify the predictions.

Keywords: Galactic cosmic rays, Galactic center, Non-thermal radiation sources, Radio continuum emission
Complex Structure of the Eastern Lobe of the Pictor A Radio Galaxy: Spectral Analysis and X-Ray/Radio Correlations. Here we present detailed analysis of the distinct X-ray emission features present within the eastern radio lobe of the Pictor A galaxy, around the jet termination region, utilizing the data obtained from the Chandra X-ray Observatory. Various emission features have been selected for the study based on their enhanced X-ray surface brightness, including five sources that appear pointlike, as well as three extended regions, one characterized by a filamentary morphology. For those, we perform a basic spectral analysis within the 0.5-7 keV range. We also investigate various correlations between the X-ray emission features and the nonthermal radio emission, utilizing the high-resolution radio maps from the Very Large Array at gigahertz frequencies. The main novel findings following from our analysis concern the newly recognized bright X-ray filament located upstream of the jet termination region, extending for at least 30 kpc (projected), and inclined with respect to the jet axis. For this feature, we observe a clear anticorrelation between the X-ray surface brightness and the polarized radio intensity, as well as a decrease in the radio rotation measure with respect to the surroundings. We speculate on the nature of the filament, in particular addressing a possibility that it is related to the presence of a hot X-ray-emitting thermal gas, only partly mixed with the nonthermal radio/X-ray-emitting electrons within the lobe, combined with the reversals in the lobe's net magnetic field.

Keywords: Radio galaxies, Non-thermal radiation sources, Relativistic jets, X-ray active galactic nuclei
The IceCube Pie Chart: Relative Source Contributions to the Cosmic Neutrino Flux. Neutrino events from IceCube have recently been associated with multiple astrophysical sources. Interestingly, these likely detections represent three distinct astrophysical source types: active galactic nuclei (AGNs), blazars, and tidal disruption events (TDEs). Here, we compute the expected contributions of AGNs, blazars, and TDEs to the overall cosmic neutrino flux detected by IceCube based on the associated events, IceCube's sensitivity, and the source types' astrophysical properties. We find that, despite being the most commonly identified sources, blazars cannot contribute more than 11% of the total flux (90% credible level), consistent with existing limits from stacked searches. On the other hand, we find that either AGNs or TDEs could contribute more than 50% of the total flux (90% credible level), although stacked searches further limit the TDE contribution to ≲30%. We also find that so-far unknown source types contribute at least 10% of the total cosmic flux with a probability of 80%. We assemble a pie chart that shows the most likely fractional contribution of each source type to IceCube's total neutrino flux.

Keywords: Neutrino astronomy, Cosmological neutrinos
Evidence for Coronal Temperature Variation in Seyfert 2 ESO 103-035 Using NuSTAR Observations. We report flux-resolved spectroscopic analysis of the active galactic nucleus (AGN) ESO 103-035 using NuSTAR observations. Following an earlier work, we fit the spectra using a thermal Comptonization model with a relativistic reflection component to obtain estimates of the coronal temperature for two flux levels. The coronal temperature was found to increase from ${24.0}_{-3.4}^{+6.8}$ to ${55.3}_{-7.2}^{+54.6}\,\mathrm{keV}$ (errors at the 1σ confidence level) as the flux increased from 9.8 to 11.9 × 10-11 erg cm-2 s-1 in the 3-78 keV band. A marginal variation in the high energy photon index allows for both a nonvarying optical depth and for the optical depth to have varied by a factor of ~2. This is in contrast to a previous work on NuSTAR flux-resolved spectroscopy of the AGN, Ark 564, where the temperature was found to decrease with flux along with a 10% variation in the optical depth. The results may be understood in a framework where AGN variability is either dominated by coronal heating variation leading to a correlated increase of temperature with flux or the opposite effect being seen when the variability is dominated by changes in the seed photon flux.

Keywords: Black hole physics, High energy astrophysics, Active galaxies, Seyfert galaxies, X-ray active galactic nuclei
Galaxy And Mass Assembly (GAMA): The Merging Potential of Brightest Group Galaxies. Using a volume-limited sample of 550 groups from the Galaxy And Mass Assembly Galaxy Group Catalogue spanning the halo mass range $12.8\lt \mathrm{log}[{M}_{h}/{M}_{\odot }]\lt 14.2$ , we investigate the merging potential of central Brightest Group Galaxies (BGGs). We use spectroscopically confirmed close-companion galaxies as an indication of the potential stellar mass buildup of low-redshift BGGs, z ≤ 0.2. We identify 17 close-companion galaxies with projected separations rp &lt; 30 kpc, relative velocities Δv ≤ 300 km s-1, and stellar mass ratios MBGG/MCC ≤ 4 relative to the BGG. These close-companion galaxies yield a total pair fraction of 0.03 ± 0.01. Overall, we find that BGGs in our sample have the potential to grow in stellar mass due to mergers by 2.2 ± 1.5% Gyr-1. This is lower than the stellar mass growth predicted by current galaxy evolution models.

Keywords: Early-type galaxies, Galaxy evolution, Galaxy groups
A Core Mass Function Indistinguishable from the Salpeter Stellar Initial Mass Function Using 1000 au Resolution ALMA Observations. We present the core mass function (CMF) of the massive star-forming clump G33.92 + 0.11 using 1.3 mm observations obtained with the Atacama Large Millimeter/submillimeter Array (ALMA). With a resolution of 1000 au, this is one of the highest resolution CMF measurements to date. The CMF is corrected by flux and number incompleteness to obtain a sample that is complete for gas masses M ≳ 2.0 M⊙. The resulting CMF is well represented by a power-law function ( ${dN}/d\mathrm{log}M\propto {M}^{{\rm{\Gamma }}}$ ), whose slope is determined using two different approaches: (i) by least-squares fitting of power-law functions to the flux- and number-corrected CMF, and (ii) by comparing the observed CMF to simulated samples with similar incompleteness. We provide a prescription to quantify and correct a flattening bias affecting the slope fits in the first approach, which is caused by small-sample or edge effects when the data are represented by either classical histograms or a kernel density estimate, respectively. The resulting slopes from both approaches are in good agreement each other, with ${\rm{\Gamma }}=-{1.11}_{-0.11}^{+0.12}$ being our adopted value. Although this slope appears to be slightly flatter than the Salpeter slope Γ = -1.35 for the stellar initial mass function (IMF), we find from Monte Carlo simulations that the CMF in G33.92 + 0.11 is statistically indistinguishable from the Salpeter representation of the stellar IMF. Our results are consistent with the idea that the form of the IMF is inherited from the CMF, at least at high masses and when the latter is observed at high enough resolution.

Keywords: Protostars, Initial mass function
Stellar Populations of Spectroscopically Decomposed Bulge-Disk for S0 Galaxies from the CALIFA Survey. We investigate the stellar population properties of bulges and disks separately for 34 S0s using integral-field spectroscopy from the Calar Alto Legacy Integral Field Area survey. The spatially resolved stellar age and metallicity of bulge and disk components are simultaneously estimated using the penalized pixel fitting method with photometrically defined weights for the two components. We find a tight correlation between age and metallicity for bulges, while the relation for disks has a larger scatter than that for bulges. This implies that the star formation histories of disks are more complicated than those of bulges. The bulges of high-mass S0s are mostly comparable in terms of metallicity, while bulges appear to be systematically more metal-rich than disks for low-mass S0s. The ages of bulges and disks in high-mass S0s appear to increase with local density. The bulge ages of low-mass S0s also increase with local density, but such a trend is not clear in the disk ages of low-mass S0s. In addition, the age difference between bulge and disk components (ΔAge) tends to increase with local density, for both high-mass and low-mass S0s. High-mass S0s have systematically greater ΔAge than low-mass S0s at a given local density. Our results indicate that the stellar mass significantly influences the evolution of S0 galaxies, but the environment also plays an important role in determining the evolution of bulges and disks at a given stellar mass.

Keywords: Galaxy ages, Extragalactic astronomy, Galaxy evolution, Galaxy environments