Sazuna/UAT_keywords huggingface dataset:
Five Massive Contact Binaries with Twin Components in LMC. Massive contact binaries refer to the close binary systems in which the components have filled their respective Roche lobes and share a common envelope with early-type spectra. Twin binaries are a special type of binary system characterized by two components with nearly equal masses. The Magellanic Cloud, comprising the Large Magellanic Cloud (LMC) and the Small Magellanic Cloud, is a fascinating galaxy that is distinct from the Milky Way. With its low metallicity, it serves as an ideal test bed for studying the formation and evolution of massive binaries and testing theoretical models. In this work, based on long-term observations with Optical Gravitational Lensing Experiment and MAssive Compact Halo Object in the LMC, we identified and performed comprehensive analyses of five massive twin contact binaries via the method of the light travel time effect and Wilson-Devinney code. The results show that all of these twin binaries are accompanied by low-mass third bodies. The third bodies have minimum masses ranging from 0.33 to 1.46 M ⊙. Their orbital periods range from 4.34 to 12.03 yr. The maximum distances between the third bodies and the central binary systems range from 6.7 to 11.4 au. Remarkably, four out of the five massive twins have evolved into deep-contact binaries, which indicates that all of them may have originated from Case A mass transfer. These results strongly suggest the significant influence of the third body in the formation and evolution of massive contact binaries and may hold the key to unraveling the origins of massive binaries.

Keywords: Eclipsing binary stars, Early-type stars, Multiple stars, Early stellar evolution
The Influence of Outflow Feedback in Clumps. We analyzed the influence of outflow feedback from two perspectives: turbulent support and potential disruptive effect, of which 694 clumps and 188 have been identified as outflow candidates. For turbulent support, we find the slopes of E turb - R clump (turbulent energy and radius of the clump) and P turb - R clump (turbulent momentum and radius of the clump) have no difference and are consistent with expected values whether there is outflow feedback in clumps or not. The ratios of the outflow energy and momentum to the turbulence energy and momentum (E flow/E turb, P flow/P turb) show that the majority of clumps have not enough energy and momentum to support turbulence. Meanwhile, there is no correlation between the velocity dispersion and radius. For potential disruptive effects, we conclude that it is impossible for the outflow activities to disrupt entire clumps and as the mass of the clumps increases, the clumps becomes harder to destroy. Finally, we do not see evidence that the virial parameter changes significantly whether the clumps have outflow candidates or not.

Keywords: Star formation, Jets, Interstellar clouds, Interstellar dynamics
The RESOLVE and ECO Gas in Galaxy Groups Initiative: The Group Finder and the Group H I─Halo Mass Relation. We present a four-step group-finding algorithm for the Gas in Galaxy Groups (G3) initiative, a spin-off of the z ∼ 0 REsolved Spectroscopy Of a Local VolumE (RESOLVE) and Environmental COntext (ECO) surveys. In preparation for future comparisons to intermediate redshift (e.g., the LADUMA survey), we design the group finder to adapt to incomplete, shallow, or nonuniform data. We use mock catalogs to optimize the group finder's performance. Compared to friends-of-friends (with false-pair splitting), the G3 algorithm offers improved completeness and halo-mass recovery with minimal loss of purity. Combining it with the volume-limited H I census data for RESOLVE and ECO, we examine the H I content of galaxy groups as a function of group halo mass. Group-integrated H I mass M H I,grp rises monotonically over halo masses M halo ∼ 1011─1014.5 M ⊙, pivoting in slope at M halo ∼ 1011.4 M ⊙, the gas-richness threshold scale. We present the first measurement of the scatter in this relation, which has a median of ∼0.3 dex and is asymmetric toward lower M H I,grp. We discuss interesting tensions with theoretical predictions and prior measurements of the M H I,grp─M halo relation. In an appendix, we release RESOLVE DR4 and ECO DR3, including updates to survey redshifts, photometry, and group catalogs, as well as a major expansion of the ECO H I inventory with value-added data products.

Keywords: Galaxy dark matter halos, Galaxy groups, Galaxy evolution, Galaxies
Predicting the Yields of z &gt; 6.5 Quasar Surveys in the Era of Roman and Rubin. About 70 luminous quasars discovered at z &gt; 6.5 are strongly biased toward the bright end, thus not providing a comprehensive view of quasar abundance beyond the cosmic dawn. We present the predicted results of the Roman/Rubin high-redshift quasar survey, yielding 3 times more, 2-4 mag deeper quasar samples, probing high-redshift quasars across a broad range of luminosities, especially faint quasars at L bol ~ 1010 L ⊙ or M 1450 ~ -22, which are currently poorly explored. We include high-z quasars, galactic dwarfs, and low-z compact galaxies with similar colors as quasar candidates. We create mock catalogs based on population models to evaluate selection completeness and efficiency. We utilize the classical color dropout method in the z and Y bands to select primary quasar candidates, followed up with the Bayesian selection method to identify quasars. We show that overall selection completeness &gt;80% and efficiency ~10% at 6.5 &lt; z &lt; 9, with 180 quasars at z &gt; 6.5, 20 at z &gt; 7.5, and 2 at z &gt; 8.5. The quasar yields depend sensitively on the assumed quasar luminosity shape and redshift evolution. Brown dwarf rejection through proper motion up to 50% can be made for stars brighter than 25 mag, low-z galaxies dominate at fainter magnitude. Our results show that Roman/Rubin are able to discover a statistical sample of the earliest and faintest quasars in the Universe. The new valuable data sets are worth follow-up studies with JWST and Extremely Large Telescopes to determine the quasar luminosity function faint end slope and constraint the supermassive black holes growth in the early Universe.

Keywords: Supermassive black holes, Wide-field telescopes, Quasars
Differential Rotation for Different-sized Sunspot Groups Early Observed by the OGAUC. Solar differential rotation is an important ingredient of the solar dynamo model, not only because the solar rotation profile is one of the key inputs in a solar dynamo model, but also because it imposes constraints for the solar dynamo model. In this study, we use the sunspot group catalog published by the Coimbra Astronomical Observatory for the period 1929-1941 to analyze solar rotation profiles of different-sized sunspot groups and the dependence of their annual average of the absolute latitude and annual average rotation rate on the solar cycle. The following main results are obtained: (1) smaller sunspot groups (with an area &lt;100 millionths of the solar hemisphere (msh)) rotate faster than larger ones (with an area &gt;500 msh); (2) different-sized sunspot groups drift toward the equator at different velocities of latitudinal drift, reflecting that they are rooted at different anchoring depths; (3) the rotation rate reaches a maximum during the minimum of the solar cycle, which seems to be independent of the size of sunspot groups. The possible mechanisms for the above results are discussed, and we infer that the differences may be due to the different anchoring depths at which flux tubes of different-sized sunspot groups are rooted, their different ages, and the different ways in which sunspot group coordinates are determined.

Keywords: Solar activity, Solar rotation, Sunspot groups
Constraining Circumgalactic Turbulence with QSO Absorption Line Measurements. Our knowledge of the circumgalactic medium (CGM) is mostly based on quasar absorption line measurements. These have uncovered a multiphase medium that is likely highly turbulent, but constraints of this turbulence are limited to measurements of the nonthermal width of absorption line components (b turb) and the line-of-sight velocity dispersion between components (σ LOS). Here we analyze a suite of CGM simulations to determine how well these indirect measures are related to the underlying CGM. Our simulations track the nonequilibrium evolution of all commonly observed ions and consist of two main types: small-scale simulations of regions of homogenous CGM turbulence and global simulations of inhomogenous turbulence throughout a galactic halo. From each simulation, we generate mock spectra of Si II, Si IV, C IV, and O VI, which allow us to directly compare b turb and σ LOS to the true line-of-sight turbulence (σ 1D). In the small-scale simulations, b turb is only weakly correlated with σ 1D, likely because it measures random motions within individual warm CGM clouds, which do not sample the overall random motions. Meanwhile, σ LOS and σ 1D are strongly correlated with σ 1D ≈ σ LOS + 10 km s-1 in the densest regions we simulated, although the strength of this correlation depended weakly on the gas phase being probed. Our large-scale simulations also indicate that b turb and σ 1D are largely uncorrelated and that σ 1D ≈ σ LOS + 10 km s-1 on average, although it varies along individual sight lines. Moreover, the σ LOS distributions from our global simulations are similar to recent observations, suggesting that this quantity may provide useful constraints on circumgalactic turbulence regardless of the axis probed.

Keywords: Hydrodynamical simulations, Astrochemistry, Galaxy kinematics, Circumgalactic medium, Magnetohydrodynamical simulations
MAXI J0637-430: A Possible Candidate for Bulk Motion Comptonization?. The transient Galactic black hole candidate MAXI J0637-430 went through an outburst in 2019-2020 for the very first time. This outburst was active for almost 6 months from 2019 November to 2020 May. We study the spectral properties of this source during that outburst using archival data from NICER/XTI, Swift/XRT, and NuSTAR/FPM satellites/instruments. We have analyzed the source during six epochs on which simultaneous NICER-NuSTAR and Swift/XRT-NuSTAR data were available. Using both phenomenological and physical model fitting approaches, we analyzed the spectral data in the broad 0.7-70 keV energy band. We first used a combination of disk blackbody with power-law, disk blackbody with broken power-law, and disk blackbody with power-law and bulk motion Comptonization (BMC) models. For a better understanding of the accretion picture, e.g., understanding how the accretion rates change with the changing size of the perceived Compton cloud, we used the two-component advective flow (TCAF) model with the broken power-law, and TCAF with the combined power-law, BMC models. For the last three epochs, the diskbb+power-law and TCAF models were able to spectrally fit the data for acceptable χ 2/degrees of freedom (dof). However, for the first three epochs, we needed an additional component to fit spectra for acceptable χ 2/dof. From our analysis, we reported on the possible presence of another component during these first three epochs when the source was in the high soft state. This additional component in this state is best described by the BMC phenomenon. From the TCAF model fitting, we estimated the average mass of the source as ${8.1}_{-2.7}^{+1.3}\,{M}_{\odot }$ .

Keywords: X-ray binary stars, Black holes, Compact radiation sources, Stellar accretion disks, Shocks
Deep Multimessenger Search for Compact Binary Mergers in LIGO, Virgo, and Fermi/GBM Data from 2016-2017. GW170817-GRB 170817A provided the first observation of gravitational waves from a neutron star merger with associated transient counterparts across the entire electromagnetic spectrum. This discovery demonstrated the long-hypothesized association between short gamma-ray bursts and neutron star mergers. More joint detections are needed to explore the relation between the parameters inferred from the gravitational wave and the properties of the gamma-ray burst signal. We developed a joint multimessenger analysis of LIGO, Virgo, and Fermi/GBM data designed for detecting weak gravitational-wave transients associated with weak gamma-ray bursts. As such, it does not start from confident (GWTC-1) events only. Instead, we take the full list of existing compact binary coalescence triggers generated with the PyCBC pipeline from the second Gravitational-Wave Observing Run (O2), and reanalyze the entire set of public Fermi/GBM data covering this observing run to generate a corresponding set of gamma-ray burst candidate triggers. We then search for coincidences between the gravitational-wave and gamma-ray burst triggers without requiring a confident detection in any channel. The candidate coincidences are ranked according to a statistic combining each candidate's strength in gravitational-wave and gamma-ray data, their time proximity, and the overlap of their sky localization. The ranking is then converted to a false alarm rate using time shifts between the gravitational-wave and gamma-ray burst triggers. We present the results using O2 triggers, which allowed us to check the validity of our method against GW170817-GRB 170817A. We also discuss the different configurations tested to maximize the significance of the joint detection.

Keywords: Neutron stars, Gamma-ray bursts, Gravitational waves
Interstellar Carbonaceous Dust Erosion Induced by X-Ray Irradiation of Water Ice in Star-forming Regions. The chemical inventory of protoplanetary midplanes is the basis for forming planetesimals. Among them, solid-state reactions based on CO/CO2 toward molecular complexity on interstellar dust grains have been studied in theoretical and laboratory work. The physicochemical interactions between ice, constituted mainly of H2O, and dust surfaces are limited to a few experimental studies focusing on vacuum ultraviolet and cosmic-ray processing. In this work, the erosion of C dust grains induced by X-ray irradiation of H2O ice was systematically investigated for the first time. The work aims to provide a better understanding of the reaction mechanism using selectively isotope-labeled oxygen/carbon species in kinetic analysis. Ultrahigh vacuum experiments were performed to study the interstellar ice analog on submicron, thick C dust at ~13 K. H2O or O2 ice was deposited on the presynthesized amorphous C dust and exposed to soft X-ray photons (250-1250 eV). Fourier-transform infrared spectroscopy was used to monitor in situ the newly formed species as a function of the incident photon fluence. Field emission scanning electron microscopy was used to monitor the morphological changes of (non-)eroded carbon samples. The X-ray processing of the ice/dust interface leads to the formation of CO2, which further dissociates and forms CO. Carbonyl groups are formed by oxygen addition to grain surfaces and are confirmed as intermediate species in the formation process. The yields of CO and CO2 were found to be dependent on the thickness of the carbon layer. The astronomical relevance of the experimental findings is discussed.

Keywords: Interstellar molecules, Dust destruction, Laboratory astrophysics, Astrochemistry, Carbonaceous grains, Interstellar dust processes
The Space Weather Context of the First Extreme Event of Solar Cycle 25, on 2022 September 5. The coronal mass ejection (CME) on 2022 September 5 was the fastest CME yet observed and measured in situ by a spacecraft inside the corona (0.06 au for the Parker Solar Probe). Here we assess the significance of this event for space weather studies by analyzing the source region characteristics and its temporal evolution via a magnetic complexity index. We also examine the kinematics and energetics of the CME. We find that it was a very fast and massive event, with a speed greater than 2200 km s-1 and a mass of 2 × 1016 g. Consequently, this is within the top 1% of all CMEs observed by SOHO/LASCO since 1996. It is therefore natural to ask, "What if this CME was an Earth-directed one?" To answer this question, we put the CME and the associated flare properties in the context of similar previous extreme events (namely, the 2012 July 23 and 2012 March 7 eruptions), discussing the possibility that these trigger a solar energetic particle (SEP) event. We find that 2022 September 5 could have resulted in a high-energy SEP event. We also estimate the transit time and speed of the CME and calculate the likely Dst variations if this was an Earth-directed event.

Keywords: Heliosphere, Solar energetic particles, Space weather, Solar coronal mass ejection shocks, Solar coronal mass ejections
A Statistical Analysis of Deflection of Coronal Mass Ejections in the Field of View of LASCO Coronagraphs. Coronal mass ejections (CMEs) can generate the most severe geomagnetic disturbances. One of the most critical factors affecting a CME's geoeffectiveness is its trajectory. It is crucial to determine whether and when CME will hit Earth. It is commonly assumed that CMEs experience a deflection of propagation in the corona and in interplanetary space. In this study, we analyze more than 14,000 CMEs listed in the Coordinate Data Analysis Workshop (CDAW) catalog during 1996-2022 to estimate their deflection in the Large and Spectrometric Coronagraph field of view (LFOV). In our statistical analysis, the deflection was determined using the CME height-time measurements listed in the CDAW catalog. We have shown that, in the solar corona, CME deflection is a common phenomenon, heavily influenced by solar activity cycles as well as phases of these cycles. We have demonstrated that during periods of solar activity minima the deflection of CMEs is mostly toward the equator, and during periods of maxima it is mostly toward the poles. This general trend of deflection is further modified by the specific structure of the magnetic field generated during successive cycles of solar activity (e.g., the asymmetry between the hemispheres). A systematic increase in deflection with time was also recognized. We have also found that the deflection increases linearly with the distance from the Sun in the LFOV (the line slope is 0.5).

Keywords: Active solar corona, Solar coronal mass ejections
BASS. XXXV. The M <SUB>BH</SUB>-σ* Relation of 105 Month Swift-BAT Type 1 AGNs. We present two independent measurements of stellar velocity dispersions (σ ⋆) from the Ca II H+K λ3969, 3934 and Mg I b λ 5183, 5172, 5167 region (3880-5550 Å) and the calcium triplet region (8350-8750 Å) for 173 hard X-ray-selected Type 1 active galactic nuclei (AGNs; z ≤ 0.08) from the 105 month Swift-BAT catalog. We construct one of the largest samples of local Type 1 AGNs that have both single-epoch virial black hole mass (M BH) estimates and σ ⋆ measurements obtained from high spectral resolution data, allowing us to test the usage of such methods for supermassive black hole studies. We find that the two independent σ ⋆ measurements are highly consistent with each other, with an average offset of only 0.002 ± 0.001 dex. Comparing M BH estimates based on broad emission lines and stellar velocity dispersion measurements, we find that the former is systematically lower by ≈0.12 dex. Consequently, Eddington ratios estimated through broad-line M BH determinations are similarly biased (but in the opposite way). We argue that the discrepancy is driven by extinction in the broad-line region. We also find an anticorrelation between the offset from the M BH-σ ⋆ relation and the Eddington ratio. Our sample of Type 1 AGNs shows a shallower M BH-σ ⋆ relation (with a power-law exponent of ≈3.5) compared with that of inactive galaxies (with a power-law exponent of ≈4.5), confirming earlier results obtained from smaller samples.

Keywords: AGN host galaxies, Supermassive black holes, Active galaxies, Galaxy bulges, X-ray active galactic nuclei, X-ray surveys, Galaxies
Two Massive, Compact, and Dust-obscured Candidate z ≃ 8 Galaxies Discovered by JWST. We present a search for extremely red, dust-obscured, z &gt; 7 galaxies with JWST/NIRCam+MIRI imaging over the first 20 arcmin2 of publicly available Cycle 1 data from the COSMOS-Web, CEERS, and PRIMER surveys. Based on their red color in F277W-F444W (~2.5 mag) and detection in MIRI/F770W (~25 mag), we identify two galaxies, COS-z8M1 and CEERS-z7M1, that have best-fit photometric redshifts of $z={8.4}_{-0.4}^{+0.3}$ and ${7.6}_{-0.1}^{+0.1}$ , respectively. We perform spectral energy distribution fitting with a variety of codes (including BAGPIPES, PROSPECTOR, BEAGLE, and CIGALE) and find a &gt;95% probability that these indeed lie at z &gt; 7. Both sources are compact (R eff ≲ 200 pc) and highly obscured (A  V  ~ 1.5-2.5) and, at our best-fit redshift estimates, likely have strong [O III]+Hβ emission contributing to their 4.4 μm photometry. We estimate stellar masses of ~1010 M ☉ for both sources; by virtue of detection in MIRI at 7.7 μm, these measurements are robust to the inclusion of bright emission lines, for example, from an active galactic nucleus. We identify a marginal (2.9σ) Atacama Large Millimeter/submillimeter Array detection at 2 mm within 0.″5 of COS-z8M1, which, if real, would suggest a remarkably high IR luminosity of ~1012 L ☉. These two galaxies, if confirmed at z ~ 8, would be extreme in their stellar and dust masses and may be representative of a substantial population of highly dust-obscured galaxies at cosmic dawn.

Keywords: Galaxy formation, High-redshift galaxies, Galaxy evolution, Galaxies
Hybrid Detection Algorithm and Study on the Quantity and Brightness Evolution Characteristics of Photospheric Bright Point Groups. Photospheric bright points (BPs), the smallest magnetic elements in the photosphere, are constantly moving and changing. Studying the characteristics of these small-scale strong magnetic fields with kilogauss magnitudes could be of significant importance for investigating the coronal heating problem. Compared to the study of a few specific BPs, investigating the collective features of BP groups can provide us with a better understanding of the overall characteristics of BPs. However, there is still a lack of research on the evolution of BP groups, and the detection algorithm of BPs still has a lot of space for improvement. We propose a hybrid BP detection model (HBD-Model) that combines traditional algorithms and deep learning to improve detection accuracy. Using the HBD-Model, we focus on studying the evolution characteristics of the quantity and brightness of BP groups at different brightness levels and how these characteristics differ between quiet and active regions. Results show that the activity of BP groups is not random or disorderly. In different brightness levels and regions, their quantity and brightness evolution exhibit periodic or complex changes.

Keywords: Solar photosphere, Astronomy data analysis, Solar magnetic bright points, Astronomy image processing
Mirror Acceleration of Cosmic Rays in a High-β Medium. In a weakly compressible high-β medium, pitch-angle scattering and the associated scattering acceleration of cosmic rays (CRs) by anisotropic Alfvén and slow modes of magnetohydrodynamic (MHD) turbulence is inefficient. To tap the energy from magnetic compressions for efficient particle acceleration, a diffusion mechanism that can effectively confine particles in space without causing their trapping or pitch-angle isotropization is needed. We find that the mirror diffusion in MHD turbulence recently identified in Lazarian &amp; Xu satisfies all the above conditions and serves as a promising diffusion mechanism for efficient acceleration of CRs via their stochastic nonresonant interactions with magnetic compressions/expansions. The resulting mirror acceleration is dominated by the slow-mode eddies with their lifetime comparable to the mirror diffusion time of CRs. Consequently, we find that the acceleration time of mirror acceleration is independent of the spatial diffusion coefficient of CRs. The mirror acceleration brings new life for the particle acceleration in a weakly compressible/incompressible medium and has important implications for studying CR reacceleration in the high-β intracluster medium.

Keywords: Magnetohydrodynamics, Intracluster medium, Cosmic rays