Sazuna/UAT_keywords huggingface dataset:
PG 1004+130: Hybrid Morphology Source or a Restarted FRII? A uGMRT Polarimetric Investigation. We present the polarization image of the hybrid morphology and broad absorption line quasar PG 1004+130 at 694 MHz obtained with the upgraded Giant Metrewave Radio Telescope. We detect linear polarization in this source's core, jets, and lobes. The visible discontinuity in total intensity between the inner jets and the kiloparsec-scale lobes suggests that the source is restarted. The inferred poloidal magnetic (B-) field structure in the inner jet is consistent with that observed in Fanaroff-Riley (FR) type II sources, as are the B-fields aligned with the lobe edges. Moreover, archival Chandra and XMM-Newton data indicate that PG 1004+130 displays several FRII-jetlike properties in X-rays. We conclude that PG 1004+130 is a restarted quasar, with both episodes of activity being FRII type. The spectral index images show the presence of an inverted spectrum core (α = +0.30 ± 0.01) and a steep spectrum inner jet (α = -0.62 ± 0.06) surrounded by much steeper lobe emission (α ≈ -1.2 ± 0.1), consistent with the suggestion that the lobes are from a previous activity episode. The spectral age difference between the two activity episodes is likely to be small (&lt;1.2 × 107 yr), in comparison to the lobe ages (~3.3 × 107 yr). The inferred B-fields in the lobes are suggestive of turbulence and the mixing of plasma. This may account for the absence of X-ray cavities around this source, similar to what is observed in M87's radio halo region. The depolarization models reveal that thermal gas of mass ~(2.4 ± 0.9) × 109 M ⊙ is mixed with the nonthermal plasma in the lobes of PG 1004+130.

Keywords: Quasars, Relativistic jets, Radio loud quasars, Fanaroff-Riley radio galaxies, Spectral index, Polarimetry
The Intracluster Light and Its Link with the Dynamical State of the Host Group/Cluster: The Role of the Halo Concentration. We investigate the role of halo concentration in the formation of intracluster light (ICL) in galaxy groups and clusters, as predicted by a state-of-the-art semianalytic model of galaxy formation, coupled with a set of high-resolution dark-matter-only simulations. The analysis focuses on how the fraction of ICL correlates with halo mass, concentration, and fraction of early-type galaxies (ETGs) in a large sample of groups and clusters with $13.0\leqslant \mathrm{log}{M}_{\mathrm{halo}}\leqslant 15.0$ . The fraction of ICL follows a normal distribution, a consequence of the stochastic nature of the physical processes responsible for the formation of the diffuse light. The fractional budget of ICL depends on both halo mass (very weakly) until group scales, and concentration (remarkably). More interestingly, the ICL fraction is higher in more concentrated objects, a result of the stronger tidal forces acting in the innermost regions of the halos where the concentration is the quantity playing the most relevant role. Our model predictions do not show any dependence between the ICL and ETGs fractions, and so we instead suggest the concentration rather than the mass, as recently claimed, to be the main driver of the ICL formation. The diffuse light starts to form in groups via stellar stripping and mergers and later assembled in more-massive objects. However, the formation and assembly keep going on group/cluster scales at lower redshift through the same processes, mainly via stellar stripping in the vicinity of the central regions where tidal forces are stronger.

Keywords: Galaxy formation
Morphology of Star-forming Clumps in Ram-pressure Stripped Galaxies as Seen by HST. We characterize the morphological properties of a statistically relevant sample of Hα and UV young star-forming clumps and optical complexes, observed with the Hubble Space Telescope in six galaxies of the GASP sample undergoing ram pressure stripping. The catalogs comprise 2406 (323 in the tails) Hα clumps, 3750 (899) UV clumps, and 424 tail optical complexes. About 15%-20% of the clumps and 50% of the complexes are resolved in size. We find that more than half of the complexes contain no Hα clumps, while most of them contain at least one UV clump. The clump number and size increase with the complex size, while the median complex filling factor is larger for UV clumps (0.27) than that for Hα clumps (0.10) and does not correlate with almost any morphological property. This suggests that the clumps' number and size grow with the complex keeping the filling factor constant. When studying the position of the clumps inside their complexes, Hα clumps, and UV clumps to a lesser extent, show a displacement from the complex center of 0.1-1 kpc, and in ~60% of the cases, they are displaced away from the galactic disk. This is in accordance with the fireball configuration, already observed in the tails of stripped galaxies. Finally, the filling factor and the clump radius increase with the distance from the galactic disk, suggesting that the reciprocal displacement of the different stellar generations increases as a consequence of the velocity gradient caused by ram pressure.

Keywords: Galaxy clusters, Star forming regions, Galaxy structure, Galaxy tails, Star formation, Galaxy evolution
Radio Plateaus in Gamma-Ray Burst Afterglows and Their Application in Cosmology. The plateau phase in radio afterglows has been observed in very few gamma-ray bursts (GRBs), and in this paper, 27 radio light curves with plateau phases were acquired from the published literature. We obtain the related parameters of the radio plateau, such as temporal indexes during the plateau phase (α 1 and α 2), break time (T b,z), and the corresponding radio flux (F b). The two-parameter Dainotti relation between the break time of the plateau and the corresponding break luminosity (L b,z) in the radio band is ${L}_{{\rm{b}},{\rm{z}}}\propto {T}_{{\rm{b}},{\rm{z}}}^{-1.20\pm 0.24}$ . Including the isotropic energy E  γ,iso and peak energy E p,i, the three-parameter correlations for the radio plateaus are written as ${L}_{{\rm{b}},{\rm{z}}}\propto {T}_{{\rm{b}},{\rm{z}}}^{-1.01\pm 0.24}{E}_{\gamma ,\mathrm{iso}}^{0.18\pm 0.09}$ and ${L}_{{\rm{b}},{\rm{z}}}\propto {T}_{{\rm{b}},{\rm{z}}}^{-1.18\pm 0.27}{E}_{{\rm{p}},{\rm{i}}}^{0.05\pm 0.28}$ , respectively. The correlations are less consistent with those of the X-ray and optical plateaus, implying that radio plateaus may have a different physical mechanism. The typical frequencies crossing the observational band may be a reasonable hypothesis that causes the breaks of the radio afterglows. We calibrate the GRB empirical luminosity correlations as a standard candle for constraining cosmological parameters and find that our samples can constrain the flat ΛCDM model well but are not sensitive to the nonflat ΛCDM model. By combining GRBs with other probes, such as supernovae and the CMB, the constraints on the cosmological parameters are Ωm = 0.297 ± 0.006 for the flat ΛCDM model and Ωm = 0.283 ± 0.008, ΩΛ = 0.711 ± 0.006 for the nonflat ΛCDM model.

Keywords: Gamma-ray bursts, Cosmological parameters
The Discovery of the Zeeman Effect in 38 GHz Class II Methanol Masers. Magnetic fields likely play an important role in star formation, but the number of directly measured magnetic field strengths remains scarce. We observed the 38.3 and 38.5 GHz Class II methanol (CH3OH) maser lines toward the high-mass star-forming region NGC 6334 F for the Zeeman effect. The observed spectral profiles have two prominent velocity features that can be further decomposed through Gaussian component fitting. In several of these fitted Gaussian components we find significant Zeeman detections, with zB los in the range from 8 to 46 Hz. If the Zeeman splitting factor z for the 38 GHz transitions is of the order of ~1 Hz mG-1, similar to that for several other CH3OH maser lines, then magnetic fields in the regions traced by these masers would be in the range of 8-46 mG. Such magnetic field values in high-mass star-forming regions agree with those detected in the better-known 6.7 GHz Class II CH3OH maser line. Since Class II CH3OH masers are radiatively pumped close to the protostar and likely occur in the accretion disk or the interface between the disk and outflow regions, such fields likely have significant impact on the dynamics of these disks.

Keywords: Interstellar molecules, High resolution spectroscopy, Spectropolarimetry, Astrosphere interstellar medium interactions, Star forming regions, Interstellar magnetic fields, Star formation, Astrophysical masers
Wrinkles in Time. I. Rapid Rotators Found in High-eccentricity Orbits. Recent space-based missions have ushered in a new era of observational astronomy, where high-cadence photometric light curves for thousands to millions of stars in the solar neighborhood can be used to test and apply stellar age-dating methods, including gyrochronology. Combined with precise kinematics, these data allow for powerful new insights into our understanding of the Milky Way's dynamical history. Using TESS data, we build a series of rotation period measurement and confirmation pipelines and test them on 1560 stars across five benchmark samples: the Pleiades, Pisces-Eridanus, Praesepe, the Hyades, and field stars from the MEarth Project. Our pipelines' recovery rates across these groups are, on average, 89%. We then apply these pipelines to 4085 likely single stars with TESS light curves in two interesting regions of Galactic action space. We identify 141 unique, rapidly rotating stars in highly eccentric orbits in the disk, some of which appear as rotationally young as the 120 Myr old Pleiades. Pending spectroscopic analysis to confirm their youth, this indicates that these stars were subject to fast-acting dynamical phenomena, the origin of which will be investigated in later papers in this series.

Keywords: Stellar kinematics, Stellar rotation, Milky Way dynamics, Stellar ages
How Nested Bars Enhance, Modulate, and Are Destroyed by Gas Inflows. Gas flows in the presence of two independently rotating nested bars remain not fully understood but are likely to play an important role in fueling the central black hole. We use high-resolution hydrodynamical simulations with detailed models of subgrid physics to study this problem. Our results show that the inner bar in double-barred galaxies can help drive gas flow from the nuclear ring to the center. In contrast, gas inflow usually stalls at the nuclear ring in single-barred galaxies. The inner bar causes a quasiperiodic inflow with a frequency determined by the difference between the two bar pattern speeds. We find that the star formation rate is higher in the model with two bars than in that with one bar. The inner bar in our model gradually weakens and dissolves due to gas inflow over a few billion years. Star formation produces metal-rich/α-poor stars, which slows the weakening of the inner bar but does not halt its eventual decay. We also present a qualitative comparison of the gas morphology and kinematics in our simulations with those of observed double-barred galaxies.

Keywords: Hydrodynamical simulations, Stellar feedback, Galaxy nuclei, Active galactic nuclei, Galaxy evolution, Interstellar medium, Barred spiral galaxies
Rotating Vector Model and Radius-to-frequency Mapping in the Presence of a Multipole Magnetic Field. The rotating vector model and radius-to-frequency mapping in the presence of a multipole magnetic field in pulsars and magnetars are considered. An axisymmetric potential field is assumed, and the following is found: (1) The radiation beam in the case of a multipole field is wider than the dipole case. This may account for the increasing pulse width at the higher frequency of pulsars (anti-radius-to-frequency mapping); (2) The expression for the polarization position angle is unchanged. Only the inclination angle α and phase constant ϕ 0 will change. The angle between the rotational axis and line of sight and the position angle constant ψ 0 will not change. When fitting the varying position angle of magnetars, these constraints should be considered. The appearance and disappearance of a multipole field may account for the changing slope of the position angle in the radio-emitting magnetar Swift J1818.0-1607. A similar but more active process in magnetar magnetospheres may account for the diverse position angle in fast radio bursts.

Keywords: Neutron stars, Magnetars, Pulsars
A Lack of 9 s Periodicity in the Follow-up NuSTAR Observation of LS 5039. The Nuclear Spectroscopic Array (NuSTAR) observed the gamma-ray binary LS 5039 for a second time in order to check for the presence of a periodic signal candidate found in the data from the previous NuSTAR observation. We do not detect the candidate signal in the vicinity of its previously reported frequency, assuming the same orbital ephemeris as in our previous paper. This implies that the previously reported periodic signal candidate was a noise fluctuation. We also perform a comparison of the lightcurves from the two NuSTAR observations and the joint spectral fitting. Our spectral analysis confirms the phase dependence found from a single NuSTAR observation at a higher significance level.

Keywords: X-ray astronomy, X-ray point sources, High mass x-ray binary stars, X-ray observatories, Magnetars
Solar Magnetic Polarity Effect on Neutron Monitor Count Rates: Comparing Latitude Surveys and Antarctic Stations. The Galactic cosmic-ray spectrum manifests pronounced variations over the 11 yr sunspot cycle and more subtle variations over the 22 yr solar magnetic cycle. An important tool to study these variations is repeated latitude surveys with neutron monitors (NMs) on board icebreakers in conjunction with land-based references. We revisit 13 annual latitude surveys from 1994 to 2007 using reference data from the Mawson NM instead of McMurdo NM (which closed in 2017). We then consider two more latitude surveys (2018 and 2019) with a monitor similar to the 3NM64 in the previous surveys but without lead rings around the central tube, a so-called "semi-leaded neutron monitor." The new surveys extend the linear relationship among data taken at different cutoff rigidity ranges. They also confirm the "crossover" measured near solar minima during epochs of opposite solar magnetic polarity and the absence of a crossover for epochs having the same solar magnetic polarity.

Keywords: Galactic cosmic rays, Solar-terrestrial interactions, Solar cycle
Phase Mixing of Propagating Alfvén Waves in a Single-fluid Partially Ionized Solar Plasma. The phase mixing of Alfvén waves is one of the most promising mechanisms for the heating of the solar atmosphere. The damping of waves in this case requires small transversal scales, relative to the magnetic field direction; this requirement is achieved by considering a transversal inhomogeneity in the equilibrium plasma density profile. Using a single-fluid approximation of a partially ionized chromospheric plasma, we study the effectiveness of the damping of phase-mixed shear Alfvén waves and investigate the effect of varying the ionization degree on the dissipation of waves. Our results show that the dissipation length of shear Alfvén waves strongly depends on the ionization degree of the plasma, but more importantly, in a partially ionized plasma, the damping length of shear Alfvén waves is several orders of magnitude shorter than in the case of a fully ionized plasma, providing evidence that phase mixing could be a large contributor to heating the solar chromosphere. The effectiveness of phase mixing is investigated for various ionization degrees, ranging from very weakly to very strongly ionized plasmas. Our results show that phase-mixed propagating Alfvén waves in a partially ionized plasma with ionization degrees in the range μ = 0.518-0.657, corresponding to heights of 1916-2150 km above the solar surface, can provide sufficient heating to balance chromospheric radiative losses in the quiet Sun.

Keywords: Space plasmas, Magnetohydrodynamics, Alfven waves, Solar magnetic fields
Solution to the Conflict between the Estimations of Resolved and Unresolved Galaxy Stellar Mass from the Perspective of JWST. By utilizing the spatially resolved photometry of galaxies at 0.2 &lt; z &lt; 3.0 in the CEERS field, we estimate the resolved and unresolved stellar mass via fitting of the spectral energy distribution (SED) to study the discrepancy between them. We first compare M * derived from photometry with and without the JWST wavelength coverage and find that M * can be overestimated by up to 0.2 dex when lacking rest-frame near-infrared (NIR) data. The SED fitting process tends to overestimate both stellar age and dust attenuation in the absence of rest-frame NIR data, consequently leading to a larger observed mass-to-light ratio and hence an elevated M *. With the inclusion of the JWST NIR photometry, we find no significant disparity between the estimates of resolved and unresolved stellar mass, providing a plausible solution to the conflict between them out to z ~ 3. Further investigation demonstrates that reliable M * estimates can be obtained, regardless of whether they are derived from spatially resolved or spatially unresolved photometry, so long as the reddest filter included in the SED fitting has a rest-frame wavelength longer than 10000 Å.

Keywords: High-redshift galaxies, Astronomy data analysis, Galaxy properties
Broadband Radio Study of the North Polar Spur: Origin of the Spectral Turnover with Insights into the X-Ray and Gamma-Ray Spectra. The North Polar Spur (NPS) is a giant structure that is clearly visible in both radio and X-ray all-sky maps. We analyzed broadband radio observations covering a range between 22 MHz and 70 GHz to systematically analyze the thermal/nonthermal emissions associated with the NPS. We demonstrate that the radio emission of the NPS comprises synchrotron, free-free, and dust emission; however, synchrotron emissions dominate over other emissions, especially at high Galactic latitudes. Moreover, the synchrotron spectra exhibit a power-law behavior with N(γ) ∝ γ -s  (s ≃ 1.8-2.4) up to a few GHz moderated by a turnover at ν brk ≃ 1 GHz, above which the spectral index s decreases by one. Assuming that the turnover is due to the electrons being cooled by synchrotron radiation before escaping (or advecting) from the emission region, the magnetic field strength can be estimated to be B ~ 8 μG if the NPS is a distant structure that is near the Galactic center (GC). However, an unreasonably strong B ~ 114 μG is required if the NPS is near the local supernova remnant (SNR). The corresponding nonthermal energy stored in the NPS is E n/th ≃ 4.4 × 1055 erg in the GC scenario, whereas E n/th ≃ 4.1 × 1052 erg is difficult to explain with a single local SNR. We also estimated the gamma-ray emission associated with the NPS through inverse Comptonization of the cosmic microwave background, which peaks at 100-1000 keV with a flux of ν F  ν  ~ 10-9 erg cm-2 s-1 sr-1 in the GC model, and may be a good candidate for detection by future X-ray/gamma-ray observatories.

Keywords: Galaxy stellar halos, Radio astronomy, Interstellar medium, Stellar wind bubbles
Mass Ratio Estimates for Overcontact Binaries Using the Derivatives of Light Curves. The photometric mass ratios of eclipsing binaries are usually estimated by light-curve modeling with an iterative method. We propose a new method for estimating the photometric mass ratio of an overcontact binary using the derivatives of a light curve, which provides a reasonable uncertainty value. The method mainly requires only the time interval value between two local extrema found in the third derivative of a light curve with no need of an iterative procedure. We applied the method to a sample of real overcontact binary data and compared the estimated mass ratios with their spectroscopically determined values. The comparison showed that our estimated mass ratios for ~67% of the samples agreed with their spectroscopic mass ratios within the estimated uncertainties, and the errors for 95% of them are within ±0.1. Our method should be useful for estimating mass ratios for numerous overcontact eclipsing binaries found with existing and future surveys, as well as for the light-curve analysis of each system.

Keywords: Eclipsing binary stars, Mass ratio, Astronomical methods, Contact binary stars
Energetics of a Solar Flare and a Coronal Mass Ejection Generated by a Hot Channel Eruption. Hot channels (HCs) are prevalent in the solar corona and play a critical role in driving flares and coronal mass ejections (CMEs). In this paper, we estimate the energy content of an X1.4 eruptive flare with a fast CME generated by an HC eruption on 2011 September 22. Originating from NOAA Active Region 11302, the HC is the most dramatic feature in 131 and 94 Å images observed by the Atmospheric Imaging Assembly (AIA) on board the Solar Dynamics Observatory (SDO). The flare is simultaneously observed by SDO/AIA, the Reuven Ramaty High-energy Solar Spectroscopic Imager, and the Extreme-ultraviolet Imager on board the "behind" Solar Terrestrial Relations Observatory (STEREO). The CME is simultaneously detected by the white-light coronagraphs of the Large Angle Spectroscopic Coronagraph on board the Solar and Heliospheric Observatory and the COR1 coronagraph on board the behind STEREO. Using multiwavelength and multiview observations of the eruption, various energy components of the HC, flare, and CME are calculated. The thermal and kinetic energies of the HC are (1.77 ± 0.61) × 1030 erg and (2.90 ± 0.79) × 1030 erg, respectively. The peak thermal energy of the flare and total radiative loss of the soft X-ray-emitting plasma are (1.63 ± 0.04) × 1031 erg and (1.03-1.31) × 1031 erg, respectively. The ratio between the thermal energies of the HC and flare is 0.11 ± 0.03, suggesting that the thermal energy of the HC is not negligible. The kinetic and potential energies of the CME are (3.43 ± 0.94) × 1031 erg and (2.66 ± 0.49) × 1030 erg, yielding a total energy of (3.69 ± 0.98) × 1031 erg for the CME. Continuous heating of the HC is required to balance the rapid cooling by heat conduction, which probably originates from intermittent magnetic reconnection at the flare current sheet. Our investigation may provide insight into the buildup, release, and conversion of energies in large-scale solar eruptions.

Keywords: Solar flares, Solar coronal mass ejections
ALMA High-frequency Long Baseline Campaign in 2021: Highest Angular Resolution Submillimeter Wave Images for the Carbon-rich Star R Lep. The Atacama Large Millimeter/submillimeter Array (ALMA) was used in 2021 to image the carbon-rich evolved star R Lep in Bands 8-10 (397-908 GHz) with baselines up to 16 km. The goal was to validate the calibration, using band-to-band (B2B) phase referencing with a close phase calibrator J0504-1512, 1.°2 from R Lep in this case, and the imaging procedures required to obtain the maximum angular resolution achievable with ALMA. Images of the continuum emission and the hydrogen cyanide (HCN) maser line at 890.8 GHz, from the J = 10-9 transition between the (1110) and (0400) vibrationally excited states, achieved angular resolutions of 13, 6, and 5 mas in Bands 8-10, respectively. Self-calibration (self-cal) was used to produce ideal images to compare with the B2B phase referencing technique. The continuum emission was resolved in Bands 9 and 10, leaving too little flux for the self-cal of the longest baselines, so these comparisons are made at coarser resolution. Comparisons showed that B2B phase referencing provided phase corrections sufficient to recover 92%, 83%, and 77% of the ideal image continuum flux densities. The HCN maser was sufficiently compact to obtain self-cal solutions in Band 10 for all baselines (up to 16 km). In Band 10, B2B phase referencing as compared to the ideal images recovered 61% and 70% of the flux density for the HCN maser and continuum, respectively.

Keywords: Submillimeter astronomy, Long baseline interferometry, Phase error