Sazuna/UAT_keywords huggingface dataset:
The Massive and Distant Clusters of WISE Survey. VIII. Radio Activity in Massive Galaxy Clusters. We present a study of the central radio activity of galaxy clusters at high redshift. Using a large sample of galaxy clusters at 0.7 &lt; z &lt; 1.5 from the Massive and Distant Clusters of Wide-field Infrared Survey Explorer Survey and the Faint Images of the Radio Sky at Twenty-Centimeters 1.4 GHz catalog, we measure the fraction of clusters containing a radio source within the central 500 kpc, which we term the cluster radio-active fraction, and the fraction of cluster galaxies within the central 500 kpc exhibiting radio emission. We find tentative (2.25σ) evidence that the cluster radio-active fraction increases with cluster richness, while the fraction of cluster galaxies that are radioluminous ( ${L}_{1.4\mathrm{GHz}}\geqslant {10}^{25}$ W Hz-1) does not correlate with richness at a statistically significant level. Compared to that calculated at 0 &lt; z &lt; 0.6, the cluster radio-active fraction at 0 &lt; z &lt; 1.5 increases by a factor of 10. This fraction is also dependent on the radio luminosity. Clusters at higher redshift are much more likely to host a radio source of luminosity ${L}_{1.4\mathrm{GHz}}\gtrsim {10}^{26}$ W Hz-1 than are lower-redshift clusters. We compare the fraction of radioluminous cluster galaxies to the fraction measured in a field environment. For 0.7 &lt; z &lt; 1.5, we find that both the cluster and field radioluminous galaxy fraction increases with stellar mass, regardless of environment, though at fixed stellar mass, cluster galaxies are roughly 2 times more likely to be radioluminous than field galaxies.

Keywords: Galaxy clusters, High-redshift galaxy clusters, Extragalactic radio sources, Active galactic nuclei, Galaxy evolution
A Two-zone Photohadronic Scenario for EHBL-like Behavior of Mrk 501. Major outbursts have been observed from the well known high-energy-peaked blazar Markarian 501 since its discovery in 1996. Two episodes of very-high-energy gamma-ray flaring events during 2005 May-July and 2012 June are of special significance, as the source exhibited extreme HBL-like behavior. The successful standard photohadronic model does not adequately explain these extraneous behaviors. We propose a two-zone photohadronic scenario to overcome this problem. In this picture, the low-energy regime (zone-1) of the spectrum follows the standard photohadronic interpretation, while the high-energy regime (zone-2) of the spectrum is new, with a spectral index δ2 ≥ 3.1, which is solely due to the extreme nature of the flaring event. We also estimate the bulk Lorentz factor corresponding to these extreme flaring events. By analyzing many flaring events before and after these extreme events we argue that the extreme HBL-like events are transient and may repeat in the future.

Keywords: Blazars, BL Lacertae objects, Gamma-rays, High energy astrophysics
The Supermassive Black Hole Masses of Reverberation-mapped Active Galactic Nuclei. Using different kinds of velocity tracers derived from the broad Hβ profile (in the mean or rms spectrum) and the corresponding virial factors f, the central supermassive black hole masses ( ${M}_{\mathrm{BH}}$ ) are calculated for a compiled sample of 120 reverberation-mapped (RM) active galactic nuclei (AGNs). For its subsample of RM AGNs with measured stellar velocity dispersion ( ${\sigma }_{* }$ ), the multivariate linear regression technique is used to calibrate the mean value f, as well as the variable FWHM-based f. It is found that, whether excluding the pseudobulges or not, the ${M}_{\mathrm{BH}}$ from the Hβ line dispersion in the mean spectrum ( ${\sigma }_{{\rm{H}}\beta ,\mathrm{mean}}$ ) has the smallest offset rms with respect to the ${M}_{\mathrm{BH}}\mbox{--}{\sigma }_{* }$ relation. For the total sample excluding SDSS-RM AGNs, with respect to ${M}_{\mathrm{BH}}$ from ${\sigma }_{* }$ or that from the Hβ line dispersion in the rms spectrum ( ${\sigma }_{{\rm{H}}\beta ,\mathrm{rms}}$ ), it is found that we can obtain ${M}_{\mathrm{BH}}$ from the ${\sigma }_{{\rm{H}}\beta ,\mathrm{mean}}$ with the smallest offset rms of 0.38 or 0.23 dex, respectively. It implies that, with respect to the Hβ FWHM, we prefer ${\sigma }_{{\rm{H}}\beta ,\mathrm{mean}}$ to calculate ${M}_{\mathrm{BH}}$ from the single-epoch spectrum. Using the FWHM-based f, we can improve the ${M}_{\mathrm{BH}}$ calculation from FWHM(Hβ) and the mean f, with a decreased offset rms from 0.52 to 0.39 dex with respect to ${M}_{\mathrm{BH}}$ from ${\sigma }_{* }$ for the subsample of 36 AGNs with ${\sigma }_{* }$ . The value of 0.39 dex is almost the same as that from ${\sigma }_{{\rm{H}}\beta ,\mathrm{mean}}$ and the mean f.

Keywords: Supermassive black holes, Quasars, Reverberation mapping, Emission line galaxies, Active galactic nuclei
Disentangling the Cosmic Web toward FRB 190608. Fast radio burst (FRB) 190608 was detected by the Australian Square Kilometre Array Pathfinder (ASKAP) and localized to a spiral galaxy at ${z}_{\mathrm{host}}=0.11778$ in the Sloan Digital Sky Survey (SDSS) footprint. The burst has a large dispersion measure ( ${\mathrm{DM}}_{\mathrm{FRB}}=339.8\,\mathrm{pc}\,{\mathrm{cm}}^{-3}$ ) compared to the expected cosmic average at its redshift. It also has a large rotation measure ( ${\mathrm{RM}}_{\mathrm{FRB}}=353\,\mathrm{rad}\,{{\rm{m}}}^{-2}$ ) and scattering timescale (τ = 3.3 ms at 1.28 GHz). Chittidi et al. perform a detailed analysis of the ultraviolet and optical emission of the host galaxy and estimate the host DM contribution to be $110\pm 37\,{\rm{p}}{\rm{c}}\,{{\rm{c}}{\rm{m}}}^{-3}$ . This work complements theirs and reports the analysis of the optical data of galaxies in the foreground of FRB 190608 in order to explore their contributions to the FRB signal. Together, the two studies delineate an observationally driven, end-to-end study of matter distribution along an FRB sightline, the first study of its kind. Combining our Keck Cosmic Web Imager (KCWI) observations and public SDSS data, we estimate the expected cosmic dispersion measure ${\mathrm{DM}}_{\mathrm{cosmic}}$ along the sightline to FRB 190608. We first estimate the contribution of hot, ionized gas in intervening virialized halos ( ${\mathrm{DM}}_{\mathrm{halos}}\approx 7\mbox{--}28\,\mathrm{pc}\,{\mathrm{cm}}^{-3}$ ). Then, using the Monte Carlo Physarum Machine methodology, we produce a 3D map of ionized gas in cosmic web filaments and compute the DM contribution from matter outside halos ( ${\mathrm{DM}}_{\mathrm{IGM}}\approx 91\mbox{--}126\,\mathrm{pc}\,{\mathrm{cm}}^{-3}$ ). This implies that a greater fraction of ionized gas along this sightline is extant outside virialized halos. We also investigate whether the intervening halos can account for the large FRB rotation measure and pulse width and conclude that it is implausible. Both the pulse broadening and the large Faraday rotation likely arise from the progenitor environment or the host galaxy.

Keywords: Galaxy dark matter halos, Quasar absorption line spectroscopy, Galaxy evolution, Intergalactic medium, Radio transient sources
Cool, Luminous, and Highly Variable Stars in the Magellanic Clouds from ASAS-SN: Implications for Thorne-Żytkow Objects and Super-asymptotic Giant Branch Stars. Stars with unusual properties can provide a wealth of information about rare stages of stellar evolution and exotic physics. However, determining the true nature of peculiar stars is often difficult. In this work, we conduct a systematic search for cool and luminous stars in the Magellanic Clouds with extreme variability, motivated by the properties of the unusual Small Magellanic Cloud star and Thorne-Żytkow Object (TŻO) candidate HV 2112. Using light curves from ASAS-SN, we identify 38 stars with surface temperatures T &lt; 4800 K, luminosities $\mathrm{log}$ (L/L⊙) &gt; 4.3, variability periods &gt;400 days, and variability amplitudes ΔV &gt; 2.5 mag. Eleven of these stars possess the distinctive double-peaked light-curve morphology of HV 2112. We use the pulsation properties and derived occurrence rates for these 12 objects to constrain their nature. From comparisons to stellar populations and models, we find that one star may be a red supergiant with large-amplitude pulsations. For the other 11 stars, we derive current masses of ∼5-10 M⊙, below the theoretical minimum mass of ∼15 M⊙ for TŻOs to be stable, casting doubt on this interpretation. Instead, we find that the temperatures, luminosities, mass-loss rates (MLRs), and periods of these stars are consistent with predictions for super-asymptotic giant branch (s-AGB) stars that have begun carbon burning but have not reached the superwind phase. We infer lifetimes in this phase of ∼(1-7) × 104 yr, also consistent with an s-AGB interpretation. If confirmed, these objects would represent the first identified population of s-AGB stars, illuminating the transition between low- and high-mass stellar evolution.

Keywords: Light curves, Massive stars, Asymptotic giant branch stars, Variable stars, Photometry, Chemically peculiar stars
The Effect of Cosmic Rays on Cometary Nuclei. II. Impact on Ice Composition and Structure. Since their formation in the protosolar nebula some ∼4.5 billion years ago, comets are in storage in cold distant regions of the solar system, the Kuiper Belt/scattered disk or Oort Cloud. Therefore, they have been considered as mostly unaltered samples of the protosolar nebula. However, a significant dose of energy is deposited by galactic cosmic rays (GCRs) into the outermost tens of meters of cometary nuclei during their stay in the Oort Cloud or Kuiper Belt. We investigate the impact of energy deposition by GCRs on cometary nuclei. We use experimental results from laboratory experiments and the energy deposition by GCRs estimated by Gronoff et al. (2020), to discuss the depth down to which the cometary nucleus is altered by GCRs. We show that GCRs do not significantly change the isotopic composition of cometary material but modify the chemical composition and the ice structure in the outer layers of the nucleus, which cannot be considered as pristine solar nebula material. We discuss the effect of the collisional history of comets on the distribution of processed material inside the nucleus and its implication on the observation of comets.

Keywords: High-energy cosmic radiation, Galactic cosmic rays, Comets, Comet interiors, Cosmic rays
Constraining the Delay Time Distribution of Compact Binary Objects from the Stochastic Gravitational-wave Background Searches. The initial separation of massive star binaries sets the timescale over which their compact remnants merge through the emission of gravitational waves. We show that the delay time distribution (DTD) of binary neutron stars or black holes can be inferred from the stochastic gravitational wave background (SGWB). If the DTD of a population is long, most of the mergers take place at low redshifts and the background would be rather quiet compared to a scenario in which the DTD is short leading to few individual detections at low redshift but a rather loud background. We show that different DTDs predict a factor of 5 difference in the magnitude of the gravitational wave background energy density ( ${{\rm{\Omega }}}_{\mathrm{GW}}$ ) and have the dominant effect on ${{\rm{\Omega }}}_{\mathrm{GW}}$ over other factors such as the mass function of the primary BH mass, $p({m}_{1})$ , the maximum considered BH mass ( ${M}_{\max }$ ), and the effective spin of the black hole ( ${\chi }_{\mathrm{eff}}$ ). A nondetection of such a background can rule out the short DTD scenario. We show that SGWB searches can rule out the short DTD scenario for the BBHs within about four years of observing time at advanced LIGO design sensitivity for a local merger rate of 30 ${\mathrm{Gpc}}^{-3}{\mathrm{yr}}^{-1}$ assuming $p({m}_{1})\propto {m}_{1}^{-1}$ , and ${M}_{\max }=50{M}_{\odot }$ .

Keywords: Neutron stars, Gravitational wave detectors, Gravitational wave sources, Gravitational wave astronomy, Gravity anomaly, Astrophysical black holes
Deviations from the Infrared-radio Correlation in Massive, Ultracompact Starburst Galaxies. Feedback through energetic outflows has emerged as a key physical process responsible for transforming star-forming galaxies into the quiescent systems observed in the local universe. To explore this process, this paper focuses on a sample of massive and compact merger remnant galaxies hosting high-velocity gaseous outflows ( $| v| \gtrsim {10}^{3}$ km s-1), found at intermediate redshift (z ∼ 0.6). From their mid-infrared emission and compact morphologies, these galaxies are estimated to have exceptionally large star formation rate (SFR) surface densities (ΣSFR ∼ 103 M⊙ yr-1 kpc-2), approaching the Eddington limit for radiation pressure on dust grains. This suggests that star formation feedback may be driving the observed outflows. However, these SFR estimates suffer from significant uncertainties. We therefore sought an independent tracer of star formation to probe the compact starburst activity in these systems. In this paper, we present SFR estimates calculated using 1.5 GHz continuum Jansky Very Large Array observations for 19 of these galaxies. We also present updated infrared (IR) SFRs calculated from WISE survey data. We estimate SFRs from the IR to be larger than those from the radio for 16 out of 19 galaxies by a median factor of 2.5. We find that this deviation is maximized for the most compact galaxies hosting the youngest stellar populations, suggesting that compact starbursts deviate from the IR-radio correlation. We suggest that this deviation stems either from free-free absorption of synchrotron emission, a difference in the timescale over which each indicator traces star formation, or exceptionally hot IR-emitting dust in these ultra-dense galaxies.

Keywords: Starburst galaxies, Stellar feedback, Compact galaxies, E+A galaxies, Star formation, Galaxy mergers, Galaxy evolution, Radio continuum emission, Radio astronomy, Luminous infrared galaxies
Validating Inversions for Toroidal Flows Using Normal-mode Coupling. Normal-mode coupling is a helioseismic technique that uses measurements of mode eigenfunctions to infer interior structure of the Sun. This technique has led to insights into the evolution and structure of toroidal flows in the solar interior. Here, we validate an inversion algorithm for normal-mode coupling by generating synthetic seismic measurements associated with input flows and comparing the input and inverted velocities. We study four different cases of input toroidal flows and compute synthetics that take into account the partial visibility of the Sun. We invert the synthetics using Subtractive Optimally Localized Averages and also try to mitigate the systematics of mode leakage. We demonstrate that, ultimately, inversions are only as good as the model we assume for the correlation between flow velocities.

Keywords: Helioseismology, Solar interior
Asteroid Thermal Inertia Estimates from Remote Infrared Observations: The Effects of Surface Roughness and Rotation Rate. The thermal inertia of an asteroid's surface can provide insight into regolith properties, such as the presence of a layer of fine dust, the density and thermal conductivity of a rocky surface, and, together with other observational data, mineralogy. Knowledge of the surface characteristics of asteroids is important for planetary defense initiatives and the extraction of resources ("asteroid mining"). A simple means of estimating asteroid thermal inertia has been proposed by Harris &amp; Drube, which is suitable for application to large sets of thermal-infrared observational data, such as those obtained by infrared space telescopes. We compare results from the Harris-Drube estimator with recently published values of asteroid thermal inertia from detailed thermophysical modeling, and provide an explanation in terms of reduced surface roughness for some discrepant results. Smooth surfaces covered in fine dust may provide an explanation for the unexpectedly low values of thermal inertia derived from thermophysical modeling for some slowly rotating main-belt asteroids. In the case of near-Earth objects (NEOs) we show that results from the estimator are in good agreement with those from thermophysical modeling, with just a few exceptions. We discuss the special cases of the NEOs (101955) Bennu, (162173) Ryugu, and (29075) 1950 DA in the context of results from our estimator. Given the data requirements and complexity of thermophysical modeling, data-analysis tools based on relatively simple concepts can play an important role in allowing "quick-look" assessment of thermal-infrared data of asteroids, especially NEOs.

Keywords: Infrared astronomy, Near-Earth objects, Main belt asteroids
An Intensity Mapping Detection of Aggregate CO Line Emission at 3 mm. We present a detection of molecular gas emission at z ∼ 1-5 using the technique of line intensity mapping. We make use of a pair of 3 mm interferometric data sets, the first from the Atacama Large Millimeter/submillimeter Array (ALMA) Spectroscopic Survey in the Hubble Ultra Deep Field, and the second from a series of Atacama Compact Array (ACA) observations conducted between 2016 and 2018, targeting the COSMOS field. At 100 GHz, we measure nonzero power at 97.8% and 99.9% confidence in the ACA and ALMA data sets, respectively. In the joint result, we reject the zero-power hypothesis at 99.99% confidence, finding ${\tilde{I}}_{s}^{2}(\nu )=770\pm 210\,\mu {{\rm{K}}}^{2}\,\mathrm{Hz}\,\mathrm{sr}$ . After accounting for sample variance effects, the estimated spectral shot power is ${\tilde{I}}_{s}^{2}(\nu )={1010}_{-390}^{+550}\,\mu {{\rm{K}}}^{2}\,\mathrm{Hz}\,\mathrm{sr}$ . We derive a model for the various line species our measurement is expected to be sensitive to, and estimate the shot power to be ${120}_{-50}^{+70}\,\mu {{\rm{K}}}^{2}\,{h}^{-3}\,{{\rm{Mpc}}}^{3}$ , ${210}_{-80}^{+110}\,\mu {{\rm{K}}}^{2}\,{h}^{-3}\,{{\rm{Mpc}}}^{3}$ , and ${100}_{-40}^{+50}\,\mu {{\rm{K}}}^{2}\,{h}^{-3}\,{{\rm{Mpc}}}^{3}$ for CO(2-1) at z = 1.3, CO(3-2) at z = 2.5, and CO(4-3) at z = 3.6, respectively. Using line ratios appropriate for high-redshift galaxies, we find these results to be in good agreement with those from the CO Power Spectrum Survey. Adopting αCO = 3.6 M☉ (K km s-1 pc2)-1, we estimate a cosmic molecular gas density of ${\rho }_{{{\rm{H}}}_{2}}(z)$ ∼ 108 M☉ Mpc-3 between z = 1-3.

Keywords: Molecular gas, Cosmological evolution, Star formation, Early universe
Phase-space Spectral Line Deconfusion in Intensity Mapping. Line intensity mapping (LIM) is a promising tool to efficiently probe the three-dimensional large-scale structure by mapping the aggregate emission of a spectral line from all sources that trace the matter density field. Spectral lines from different redshifts can fall in the same observed frequency and be confused, however, which is a major challenge in LIM. In this work, we develop a line deconfusion technique in map space capable of reconstructing the three-dimensional spatial distribution of line-emitting sources. If multiple spectral lines of a source population are observable in multiple frequencies, using the sparse approximation, our technique iteratively extracts sources along a given line of sight by fitting the LIM data to a set of spectral templates. We demonstrate that the technique successfully extracts sources with emission lines present at a few σ above the noise level, taking into account uncertainties in the source modeling and presence of continuum foreground contamination and noise fluctuations. As an example, we consider a Tomographic Ionized-carbon Mapping Experiment/CarbON C II line in post-rEionisation and ReionisaTiOn epoch (TIME/CONCERTO)-like survey targeting [C II] at the epoch of reionization, and reliably reconstruct the 3D spatial distribution of the CO interlopers and their luminosity functions at 0.5 ≲ z ≲ 1.5. We also demonstrate a successful deconfusion for the Spectro-Photometer for the History of the Universe, Epoch of Reionization, and Ices Explorer (SPHEREx) mission in the near-infrared wavelengths. We discuss a formalism in which the reconstructed maps can be further cross-correlated with a (galaxy) tracer population to estimate the total interloper power. This technique is a general framework to extract the phase-space distribution of low-redshift interlopers, without the need of external information, for any line deconfusion problem.

Keywords: Diffuse radiation, Observational cosmology, Large-scale structure of the universe
The Carnegie Supernova Project-I: Correlation between Type Ia Supernovae and Their Host Galaxies from Optical to Near-infrared Bands. We present optical and near-infrared (NIR) (ugriYJH) photometry of host galaxies of Type Ia supernovae (SN Ia) observed by the Carnegie Supernova Project-I. We determine host galaxy stellar masses and, for the first time, study their correlation with SN Ia standardized luminosity across optical and NIR (uBgVriYJH) bands. In the individual bands, we find that SNe Ia are more luminous in more massive hosts with luminosity offsets ranging between -0.07 ± 0.03 and -0.15 ± 0.04 mag after light-curve standardization. The slope of the SN Ia Hubble residual-host mass relation is negative across all uBgVriYJH bands with values ranging between -0.029 ± 0.029 and -0.093 ± 0.031 mag dex-1—implying that SNe Ia in more massive galaxies are brighter than expected. The near-constant observed correlations across optical and NIR bands indicate that dust may not play a significant role in the observed luminosity offset-host mass correlation. We measure projected separations between SNe Ia and their host centers, and find that SNe Ia that explode beyond a projected 10 kpc have a 50%- 60% reduction of the dispersion in Hubble residuals across all bands—making them a more uniform subset of SNe Ia. Dust in host galaxies, peculiar velocities of nearby SN Ia, or a combination of both may drive this result as the color excesses of SNe Ia beyond 10 kpc are found to be generally lower than those interior, but there is also a diminishing trend of the dispersion as we exclude nearby events. We do not find that SN Ia average luminosity varies significantly when they are grouped in various host morphological types. Host galaxy data from this work will be useful, in conjunction with future high-redshift samples, in constraining cosmological parameters. * This paper includes data gathered with the 6.5 m Magellan Telescopes located at Las Campanas Observatory, Chile.

Keywords: Observational cosmology, Type Ia supernovae, Galaxy photometry, Galaxies
Grain Formation around the AGB Star L<SUB>2</SUB> Puppis Based On ALMA Observations. While models of grain formation in the outflows of carbon-rich stars have been relatively successful, models of outflows from oxygen-rich, asymptotic giant branch stars have been less fortunate. Under current modeling, it is difficult to produce sufficient amounts of silicate grains with high enough opacity to form a dust-driven wind from these stars. To investigate the cause of this difference, this work is a comparison between typical outflow model results and a model using input from Atacama Large Millimeter/submillimeter Array observations of L2 Puppis. The temperatures from these observations are much lower than would typically be used in the standard outflow model. In addition, the observed gas densities are much higher than predicted from typical outflow models. Both of these differences make the formation of silicate grains much more favorable than predicted in current outflow models. We then explore the effects of other possible nonideal conditions including the efficiency of cluster growth prior to nucleation, the efficiency of grain growth following nucleation and the variation of grain coupling to stellar radiation during grain growth. Finally, we calculate the potential enhancement in grain production based on possible increased refractory abundances resulting from the vaporization of millimeter-scale and larger particles left over from the presence of a former planetary system.

Keywords: Circumstellar envelopes, Asymptotic giant branch stars, Circumstellar dust