Sazuna/UAT_keywords huggingface dataset:
The JCMT BISTRO Survey: Magnetic Fields Associated with a Network of Filaments in NGC 1333. We present new observations of the active star formation region NGC 1333 in the Perseus molecular cloud complex from the James Clerk Maxwell Telescope B-Fields In Star-forming Region Observations (BISTRO) survey with the POL-2 instrument. The BISTRO data cover the entire NGC 1333 complex (∼1.5 pc × 2 pc) at 0.02 pc resolution and spatially resolve the polarized emission from individual filamentary structures for the first time. The inferred magnetic field structure is complex as a whole, with each individual filament aligned at different position angles relative to the local field orientation. We combine the BISTRO data with low- and high- resolution data derived from Planck and interferometers to study the multiscale magnetic field structure in this region. The magnetic field morphology drastically changes below a scale of ∼1 pc and remains continuous from the scales of filaments (∼0.1 pc) to that of protostellar envelopes (∼0.005 pc or ∼1000 au). Finally, we construct simple models in which we assume that the magnetic field is always perpendicular to the long axis of the filaments. We demonstrate that the observed variation of the relative orientation between the filament axes and the magnetic field angles are well reproduced by this model, taking into account the projection effects of the magnetic field and filaments relative to the plane of the sky. These projection effects may explain the apparent complexity of the magnetic field structure observed at the resolution of BISTRO data toward the filament network.

Keywords: Interstellar filaments, Interstellar magnetic fields, Star formation, Interstellar medium, Submillimeter astronomy, Polarimetry
TOI-1728b: The Habitable-zone Planet Finder Confirms a Warm Super-Neptune Orbiting an M-dwarf Host. We confirm the planetary nature of TOI-1728b using a combination of ground-based photometry, near-infrared Doppler velocimetry and spectroscopy with the Habitable-zone Planet Finder. TOI-1728 is an old, inactive M0 star with Teff = ${3980}_{-32}^{+31}$ K, which hosts a transiting super-Neptune at an orbital period of ∼3.49 days. Joint fitting of the radial velocities and TESS and ground-based transits yields a planetary radius of ${5.05}_{-0.17}^{+0.16}$ R⊕, mass ${26.78}_{-5.13}^{+5.43}$ M⊕, and eccentricity ${0.057}_{-0.039}^{+0.054}$ . We estimate the stellar properties, and perform a search for He 10830 Šabsorption during the transit of this planet and claim a null detection with an upper limit of 1.1% with 90% confidence. A deeper level of He 10830 Šabsorption has been detected in the planet atmosphere of GJ 3470b, a comparable gaseous planet. TOI-1728b is the largest super-Neptune—the intermediate subclass of planets between Neptune and the more massive gas-giant planets—discovered around an M dwarf. With its relatively large mass and radius, TOI-1728 represents a valuable data point in the M-dwarf exoplanet mass-radius diagram, bridging the gap between the lighter Neptune-sized planets and the heavier Jovian planets known to orbit M dwarfs. With a low bulk density of ${1.14}_{-0.24}^{+0.26}$ g cm-3, and orbiting a bright host star (J ∼ 9.6, V ∼ 12.4), TOI-1728b is also a promising candidate for transmission spectroscopy both from the ground and from space, which can be used to constrain planet formation and evolutionary models.

Keywords: Exoplanet detection methods, Radial velocity, Planet hosting stars
New High-quality Strong Lens Candidates with Deep Learning in the Kilo-Degree Survey. We report new high-quality galaxy-scale strong lens candidates found in the Kilo-Degree Survey data release 4 using machine learning. We have developed a new convolutional neural network (CNN) classifier to search for gravitational arcs, following the prescription by Petrillo et al. and using only r-band images. We have applied the CNN to two "predictive samples": a luminous red galaxy (LRG) and a "bright galaxy" (BG) sample (r &lt; 21). We have found 286 new high-probability candidates, 133 from the LRG sample and 153 from the BG sample. We have ranked these candidates based on a value that combines the CNN likelihood of being a lens and the human score resulting from visual inspection (P-value), and here we present the highest 82 ranked candidates with P-values ≥0.5. All of these high-quality candidates have obvious arc or pointlike features around the central red defector. Moreover, we define the best 26 objects, all with P-values ≥0.7, as a "golden sample" of candidates. This sample is expected to contain very few false positives; thus, it is suitable for follow-up observations. The new lens candidates come partially from the more extended footprint adopted here with respect to the previous analyses and partially from a larger predictive sample (also including the BG sample). These results show that machine-learning tools are very promising for finding strong lenses in large surveys and more candidates can be found by enlarging the predictive samples beyond the standard assumption of LRGs. In the future, we plan to apply our CNN to the data from next-generation surveys such as the Large Synoptic Survey Telescope, Euclid, and the Chinese Space Station Optical Survey.

Keywords: Elliptical galaxies, Strong gravitational lensing, Gravitational lensing, Dark matter
The Power Spectra of Polarized, Dusty Filaments. We develop an analytic model for the power spectra of polarized filamentary structures as a way to study the Galactic polarization foreground to the cosmic microwave background. Our approach is akin to the cosmological halo-model framework, and reproduces the main features of the Planck 353 GHz power spectra. We model the foreground as randomly oriented, three-dimensional, spheroidal filaments, accounting for their projection onto the sky. The main tunable parameters are the distribution of filament sizes, the physical aspect ratio of filaments, and the dispersion of the filament axis around the local magnetic field direction. The abundance and properties of filaments as a function of size determine the slopes of the foreground power spectra, as we show via scaling arguments. The filament aspect ratio determines the ratio of B-mode power to E-mode power, and specifically reproduces the Planck-observed dust ratio of one-half when the short axis is roughly one-fourth the length of the long axis. Filament misalignment to the local magnetic field determines the TE cross-correlation, and to reproduce Planck measurements we need a (three-dimensional) misalignment angle with an rms dispersion of about 50°. These parameters are not sensitive to the particular filament density profile. By artificially skewing the distribution of the misalignment angle, this model can reproduce the Planck-observed (and parity-violating) TB correlation. The skewing of the misalignment angle necessary to explain TB will cause a yet-unobserved, positive EB dust correlation, a possible target for future experiments.

Keywords: Cosmic microwave background radiation, Interstellar medium
Laboratory Optical Spectroscopy of Vibronic Transitions of the Thiophenoxy Radical. The thiophenoxy radical (C6H5S) is a species of possible astrophysical interest due to an electronic transition in a 5000 Å region. The ${B}^{2}{A}_{2}\leftarrow {X}^{2}{B}_{1}$ electronic transition of this radical in the discharge of thiophenol was measured using a cavity ring-down spectrometer. The optical absorption spectrum of this transition was obtained in the range covering from the origin band (0-0) to a frequency of 1750 cm-1. The vibronic bands in the 400-1700 cm-1 region are stronger than the origin band, suggesting structural difference between the ground and excited electronic states. The prominent progression was assigned to the 6a symmetric in-plane C-C-C bending mode starting from the $6{{\rm{b}}}_{0}^{1}$ forbidden band. Band origins of individual bands were determined by analysis of the rotational profiles. Although these vibronic bands were not found in optical spectra of diffuse clouds, the upper limits of the column densities for the thiophenoxy radical in the diffuse clouds toward HD 183143 and HD 204827 were evaluated to be ∼4 × 1013 cm-2.

Keywords: Diffuse interstellar bands
Can the Kappa-distributed Electron Energies Account for the Intensity Ratios of O II Lines in Photoionized Gaseous Nebulae?. A vexing puzzle in the study of planetary nebulae and H II regions is that the plasma diagnostic results based on collisionally excited lines systematically differ from those based on recombination lines. A fairly speculative interpretation is the presence of nonthermal electrons with the so-called κ energy distributions, yet there is little observational evidence to verify or disprove this hypothesis. In this paper, we examine the influence of κ-distributed electrons on the emissivities of O II recombination lines using an approximate method, where the rate coefficients for a κ distribution are computed by summing Maxwellian-Boltzmann rate coefficients with appropriate weights. The results show that if invoking κ-distributed electrons, the temperatures derived from the [O III] (λ4959 + λ5007)/λ4363 ratios could coincide with those estimated from the O II λ4649/λ4089 ratios. However, the estimated temperatures and κ values are not in agreement with those obtained through comparing the [O III] (λ4959 + λ5007)/λ4363 ratios and the hydrogen recombination spectra, suggesting that the electron energy is unlikely to follow the κ-distributions over a global scale of the nebular regions. Nevertheless, based on this observation alone, we cannot definitely rule out the presence of κ-distributed electrons in some microstructures within nebulae.

Keywords: Atomic spectroscopy, Planetary nebulae, H II regions, Plasma astrophysics
An Eruptive Circular-ribbon Flare with Extended Remote Brightenings. We study an eruptive X1.1 circular-ribbon flare on 2013 November 10, combining multiwavelength observations with a coronal field reconstruction using a non-force-free field method. In the first stage, a filament forms via magnetic reconnection between two mildly twisted sheared arcades, which are embedded under the fan dome associated with a null point (NP). This reconnection seems to be driven by photospheric shearing and converging flows around the inner two arcade footpoints, consistent with the flare-related changes of the transverse field. The southern portion of the filament rises upward due to torus instability and pushes against the NP. The induced NP reconnection then generates the circular ribbon and the initial remote brightening in the west, as accelerated electrons precipitate along the fan and propagate outward along quasi-separatix surfaces with high values of the squashing factor (Q) in the envelope fields, which have a curtain-like shape here. In the second stage, the southern end of the flux rope breaks away from the surface, sequentially disrupts the dome and overlying fields, and erupts in a whipping-like fashion to become a partial halo coronal mass ejection. This leads to an enhanced flare emission and fast-moving remote brightenings at the footpoints of the magnetic curtain, which span a remarkably broad region and are also associated with coronal dimmings. This is a rare example of eruptive circular-ribbon flares, in which the evolution of a flux rope from its formation to successful eruption out of the dome and the resulting unusually extended remote brightenings are completely observed.

Keywords: Solar activity, Solar coronal mass ejections, Solar flares, Solar magnetic fields
Search for Optically Dark Infrared Galaxies without Counterparts of Subaru Hyper Suprime-Cam in the AKARI North Ecliptic Pole Wide Survey Field. We present the physical properties of AKARI sources without optical counterparts in optical images from the Hyper Suprime-Cam (HSC) on the Subaru telescope. Using the AKARI infrared (IR) source catalog and HSC optical catalog, we select 583 objects that do not have HSC counterparts in the AKARI North Ecliptic Pole wide survey field (∼5 deg2). Because the HSC limiting magnitude is deep (gAB ∼ 28.6), these are good candidates for extremely red star-forming galaxies (SFGs) and/or active galactic nuclei (AGNs), possibly at high redshifts. We compile multiwavelength data out to 500 μm and use them for fitting the spectral energy distribution with CIGALE to investigate the physical properties of AKARI galaxies without optical counterparts. We also compare their physical quantities with AKARI mid-IR selected galaxies with HSC counterparts. The estimated redshifts of AKARI objects without HSC counterparts range up to z ∼ 4, significantly higher than for AKARI objects with HSC counterparts. We find that (i) 3.6 - 4.5 μm color, (ii) AGN luminosity, (iii) stellar mass, (iv) star formation rate, and (v) V-band dust attenuation in the interstellar medium of AKARI objects without HSC counterparts are systematically larger than those of AKARI objects with counterparts. These results suggest that our sample includes luminous, heavily dust-obscured SFGs/AGNs at z ∼ 1-4 that are missed by previous optical surveys, providing very interesting targets for the coming era of the James Webb Space Telescope.

Keywords: Bayesian statistics, Active galactic nuclei, Infrared galaxies, Infrared photometry
Fallback Rates from Partial Tidal Disruption Events. A tidal disruption event (TDE) occurs when a star plunges through a supermassive black hole's tidal radius, at which point the star's self-gravity is overwhelmed by the tidal gravity of the black hole. In a partial TDE, where the star does not reach the full disruption radius, only a fraction of the star's mass is tidally stripped while the rest remains intact in the form of a surviving core. Analytical arguments have recently suggested that the temporal scaling of the fallback rate of debris to the black hole asymptotes to t-9/4 for partial disruptions, effectively independently of the mass of the intact core. We present hydrodynamical simulations that verify the existence of this predicted, t-9/4 scaling. We also define a break timescale—the time at which the fallback rate transitions from a t-5/3 scaling to the characteristic t-9/4 scaling—and measure this break timescale as a function of the impact parameter and the surviving core mass. These results deepen our understanding of the properties and breadth of possible fallback curves expected from TDEs and will therefore facilitate more accurate interpretation of data from wide-field surveys.

Keywords: Black hole physics, Hydrodynamics, Galaxy nuclei
A Comparison of the Stellar, CO, and Dust-continuum Emission from Three Star-forming HUDF Galaxies at z ∼ 2. We compare the extent of the dust, molecular gas, and stars in three star-forming galaxies, at z = 1.4, 1.6, and 2.7, selected from the Hubble Ultra Deep Field based on their bright carbon monoxide (CO) and dust-continuum emission as well as their large rest-frame optical sizes. The galaxies have high stellar masses, ${M}_{* }\gt {10}^{11}{M}_{\odot }$ , and reside on, or slightly below, the main sequence of star-forming galaxies at their respective redshifts. We probe the dust and molecular gas using subarcsecond Atacama Large Millimeter/submillimeter Array observations of the 1.3 mm continuum and CO line emission, respectively, and probe the stellar distribution using Hubble Space Telescope observations at 1.6 μm. We find that for all three galaxies the CO emission appears ≳30% more compact than the stellar emission. For the z = 1.4 and 2.7 galaxies, the dust emission is also more compact, by ≳50%, than the stellar emission, whereas for the z = 1.6 galaxy, the dust and stellar emission have similar spatial extents. This similar spatial extent is consistent with observations of local disk galaxies. However, most high-redshift observations show more compact dust emission, likely because of the ubiquity of central starbursts at high redshift and the limited sensitivity of many of these observations. Using the CO emission line, we also investigate the kinematics of the cold interstellar medium in the galaxies, and find that all three have kinematics consistent with a rotation-dominated disk.

Keywords: Molecular gas, High-luminosity active galactic nuclei, Dust continuum emission, Galaxy evolution, Interstellar medium
Asteroseismic Analyses of Slowly Pulsating B Star KIC 8324482: Ultraweak Element Mixing beyond the Central Convective Core. Asteroseismology is a powerful tool for probing the inner structure and determining the evolutionary status and the fundamental parameters of stars. The oscillation spectra of slowly pulsating B (SPB) stars show almost uniform period spans, whose pattern is sensitive to the structure of the μ-gradient shell beyond the central convective core and hence can be used to efficiently describe their shapes and constrain the convective core. The SPB star KIC 8324482 was observed by Kepler for over 1470 days with a long-cadence pattern. Nearly equidistant period spacing patterns are found for the 14 connective dipolar modes that are extracted from the oscillation spectrum by Zhang et al. In the present work, we analyze them in depth with the χ2-matching method and determine their χ2-minimization models (CMMs). Based on those calculated CMMs, we find that KIC 8324482 is a young ( ${t}_{\mathrm{age}}={20.96}_{-1.28}^{+3.85}$ Myr), metal-poor ( $[\mathrm{Fe}/{\rm{H}}]=-0.6.{9}_{-0.115}^{+0.176}$ dex), and intermediate-mass ( $M={6.075}_{-0.2500}^{+0.1375}\,{M}_{\odot }$ ) star with a convective core of ${M}_{\mathrm{CC}}={1.338}_{-0.091}^{+0.057}\,{M}_{\odot }$ in mass and ${R}_{\mathrm{CC}}={0.5175}_{-0.0103}^{+0.0048}\,{R}_{\odot }$ in radius and with a surface rotation velocity ${V}_{\mathrm{eq}}={2.61}_{-0.11}^{+0.13}\,\mathrm{km}\,{{\rm{s}}}^{-1}$ . The central hydrogen abundance is of ${X}_{{\rm{C}}}={0.5046}_{-0.0074}^{+0.0018}$ . Asteroseismic analyses indicate that the "propagation time" of g-mode in KIC 8324482 is of ${{\rm{\Lambda }}}_{0}\,={276.85}_{-0.47}^{+1.26}$ μHz. To well match with the observed period spacing pattern, an extra diffusion mixing ( $\mathrm{log}{D}_{\mathrm{mix}}={3.125}_{-0.250}^{+0.125}$ ) should be considered, but the normal core overshooting fov must be fixed as zero in the best-fitting model. Such ultraweak mixing beyond the convective core corresponds to a fast rotation that is about 20-30 times the asteroseismic suggested rotation Ωrot ≃ 0.2 μHz, if it is thought of as shear mixing induced completely by differential rotation.

Keywords: Stellar interiors, Stellar structures, B stars, Stellar properties, Fundamental parameters of stars, Stellar oscillations, Stellar rotation, Asteroseismology
The Invariance of the Diffusion Coefficient with Iterative Operations of the Charged Particle Transport Equation. The spatial parallel diffusion coefficient (SPDC) is one of the important quantities describing energetic charged particle transport. There are three different definitions for the SPDC: the displacement variance definition ${\kappa }_{{zz}}^{\mathrm{DV}}={\mathrm{lim}}_{t\to {t}_{\infty }}d{\sigma }^{2}/(2{dt})$ , the Fick's law definition ${\kappa }_{{zz}}^{\mathrm{FL}}=J/X$ with $X=\partial F/\partial z$ , and the Taylor-Green-Kubo (TGK) formula definition ${\kappa }_{{zz}}^{\mathrm{TGK}}={\int }_{0}^{\infty }{dt}\langle {v}_{z}(t){v}_{z}(0)\rangle $ . For a constant mean magnetic field, the three different definitions of the SPDC give the same result. However, for a focusing field, it is demonstrated that the results of the different definitions are not the same. In this paper, from the Fokker-Planck equation, we find that different methods, e.g., the general Fourier expansion and iteration method, can give different equations of the isotropic distribution function (EIDFs). But it is shown that one EIDF can be transformed into another by some derivative iterative operations (DIOs). If one definition of the SPDC is invariant for the DIOs, it is clear that the definition is also invariant for different EIDFs; therefore, it is an invariant quantity for the different derivation methods of the EIDF. For the focusing field, we suggest that the TGK definition ${\kappa }_{{zz}}^{\mathrm{TGK}}$ is only an approximate formula, and the Fick's law definition ${\kappa }_{{zz}}^{\mathrm{FL}}$ is not invariant to some DIOs. However, at least for the special condition, in this paper we show that the definition ${\kappa }_{{zz}}^{\mathrm{DV}}$ is an invariant quantity to the DIOs. Therefore, for a spatially varying field, the displacement variance definition ${\kappa }_{{zz}}^{\mathrm{DV}}$ , rather than the Fick's law definition ${\kappa }_{{zz}}^{\mathrm{FL}}$ and TGK formula definition ${\kappa }_{{zz}}^{\mathrm{TGK}}$ , is the most appropriate definition of the SPDCs.

Keywords: Interplanetary turbulence, Interplanetary magnetic fields, Particle astrophysics, Cosmic rays
The 21 cm kSZ-kSZ Bispectrum during the Epoch of Reionization. Current and next-generation radio interferometers such as the Hydrogen Epoch of Reionization Array (HERA) and Square Kilometre Array are projected to measure the 21 cm auto-power spectrum from the Epoch of Reionization (EoR). Another observational signal of this era is the kinetic Sunyaev-Zel'dovich (kSZ) signal in the cosmic microwave background (CMB), which will be observed by the upcoming Simons Observatory (SO) and CMB-S4 experiments. The 21 cm signal and the contribution to the kSZ from the EoR are expected to be anticorrelated. However, the naïve cross-correlation between the kSZ and 21 cm maps suffers from significant cancellation. We present here an investigation of the 21 cm kSZ-kSZ bispectrum, which should not suffer the same cancellation as the simple two-point cross-correlation. We show that there is a significant and nonvanishing signal that is sensitive to the reionization history. In the absence of foreground contamination, we forecast that this signal is detectable at high statistical significance with HERA and SO. However, the bispectrum we study suffers from the fact that the kSZ signal is sensitive only to Fourier modes with long-wavelength line-of-sight components, which are generally lost in the 21 cm data sets owing to foreground contamination. We discuss possible strategies for alleviating this contamination, including an alternative four-point statistic that may help circumvent this issue.

Keywords: Cosmology, Cosmic microwave background radiation, Sunyaev-Zeldovich effect, Intergalactic medium, Reionization