Sazuna/UAT_keywords huggingface dataset:
Properties of PSR J1023+0038 Based on Kepler, TESS, and FAST. The pulsar system PSR J1023+0038 is a very interesting binary with radio millisecond pulsar and low-mass X-ray binary transitions, which depend on the stellar accretion process. We have used Kepler light curves with 1 minute cadence and TESS light curves with 2 minute cadence to study the flare properties of PSR J1023+0038. We detected 516 flare events in the K2 data and 84 flare events in the TESS survey data. We determined the flare rise and delay times, the flare durations and amplitudes, and flare energies. We obtained a value of the power-law index of 0.359 ± 0.023 between the flare energies and decay times, which is similar to the theoretically predicted value of 1/3. This in turn indicates that PSR J1023+0038 might be exhibiting physical mechanisms described by magnetic reconnection theory. Using the maximum likelihood estimation method, we also calculated the power-law index of the cumulative flare frequency distribution, finding 1.87 ± 0.27 for the Kepler data and 1.74 ± 0.29 for the TESS data. Meanwhile, we reduced six FAST observations of PSR J1023+0038 from 2019-2021 using a standard pulsar search procedure. We report that we detected a prompt signal with a period compatible with that found in previous observations of PSR J1023+0038. However, there are several reasons (statistical, excess DM, pulse shape, etc.) as to why the association is not likely.

Keywords: Stellar flares, Pulsars, Stellar activity
Gamma-Ray Burst Observations by the High-Energy Particle Detector on board the China Seismo-Electromagnetic Satellite between 2019 and 2021. In this paper we report the detection of five strong gamma-ray bursts (GRBs) by the High-Energy Particle Detector (HEPD-01) mounted on board the China Seismo-Electromagnetic Satellite, operational since 2018 on a Sun-synchronous polar orbit at a ~507 km altitude and 97° inclination. HEPD-01 was designed to detect high-energy electrons in the energy range 3-100 MeV, protons in the range 30-300 MeV, and light nuclei in the range 30-300 MeV n-1. Nonetheless, Monte Carlo simulations have shown HEPD-01 is sensitive to gamma-ray photons in the energy range 300 keV-50 MeV, even if with a moderate effective area above ~5 MeV. A dedicated time correlation analysis between GRBs reported in literature and signals from a set of HEPD-01 trigger configuration masks has confirmed the anticipated detector sensitivity to high-energy photons. A comparison between the simultaneous time profiles of HEPD-01 electron fluxes and photons from GRB190114C, GRB190305A, GRB190928A, GRB200826B, and GRB211211A has shown a remarkable similarity, in spite of the different energy ranges. The high-energy response, with peak sensitivity at about 2 MeV, and moderate effective area of the detector in the actual flight configuration explain why these five GRBs, characterized by a fluence above ~3 × 10-5 erg cm-2 in the energy interval 300 keV-50 MeV, have been detected.

Keywords: Cosmic ray detectors, Gamma-ray bursts, Particle astrophysics
Formation of Interstellar Complex Organic Molecules on Water-rich Ices Triggered by Atomic Carbon Freezing. The reactivity of interstellar carbon atoms (C) on water-dominated ices is one of the possible ways to form interstellar complex organic molecules (iCOMs). In this work, we report a quantum chemical study of the coupling reaction of C (3P) with an icy water molecule, alongside possible subsequent reactions with the most abundant closed-shell frozen species (NH3, CO, CO2, and H2), atoms (H, N, and O), and molecular radicals (OH, NH2, and CH3). We found that C reacts spontaneously with the water molecule, resulting in the formation of 3C-OH2, a highly reactive species due to its triplet electronic state. While reactions with the closed-shell species do not show any reactivity, reactions with N and O form CN and CO, respectively, the latter ending up in methanol upon subsequent hydrogenation. The reactions with OH, CH3, and NH2 form methanediol, ethanol, and methanimine, respectively, upon subsequent hydrogenation. We also propose an explanation for methane formation observed in experiments through additions of H to C in the presence of ices. The astrochemical implications of this work are: (i) atomic C on water ice is locked into 3C-OH2, making difficult the reactivity of bare C atoms on icy surfaces, contrary to what is assumed in current astrochemical models; and (ii) the extraordinary reactivity of 3C-OH2 provides new routes toward the formation of iCOMs in a nonenergetic way, in particular ethanol, the mother of other iCOMs once it is in the gas phase.

Keywords: Interstellar molecules, Interstellar dust, Reaction rates, Astrochemistry, Computational methods, Surface ices, Interstellar medium, Complex organic molecules
Opacities of S-type Stars: The Singlet B <SUP>1</SUP>Π-X <SUP>1</SUP>Σ<SUP>+</SUP>, B <SUP>1</SUP>Π-A <SUP>1</SUP>△, and C <SUP>1</SUP>Σ<SUP>+</SUP>-X <SUP>1</SUP>Σ<SUP>+</SUP> Band Systems of ZrO. The ZrO B 1Π-X 1Σ+, B 1Π-A 1Δ, and C 1Σ+-X 1Σ+ band systems are important opacity sources in the near-infrared and optical spectra of S-type stars. A total of 21 rovibronic bands with v″ ≤ 7 and $v^{\prime} \leqslant 5$ were observed and fit for the B 1Π-X 1Σ+ transition, five bands for the 90ZrO B 1Π-A 1Δ transition and one band for the 90ZrO C 1Σ+-X 1Σ+ transition. All band systems were analyzed using high-temperature, high-resolution emission spectra collected at the National Solar Observatory (Kitt Peak). A modern spectroscopic analysis was performed using the PGOPHER program to provide updated spectroscopic constants. In general, we improve the accuracy of the line positions reported in the literature and slightly extend the vibrational analysis. Equilibrium molecular constants were then derived and combined with new ab initio calculations of transition dipole moment functions to produce line lists with line strengths.

Keywords: Spectral line lists, Molecular spectroscopic constants, Rotational spectroscopy
DIISC-III. Signatures of Stellar Disk Growth in Nearby Galaxies. We explore the growth of the stellar disks in 14 nearby spiral galaxies as part of the Deciphering the Interplay between the Interstellar medium, Stars, and the Circumgalactic medium (DIISC) survey. We study the radial distribution of specific star formation rates (sSFRs) and investigate the ratio of the difference in the outer and inner sSFRs (ΔsSFR = sSFRout - sSFRin) of the disk and the total sSFR, ΔsSFR/sSFR, to quantify disk growth. We find ΔsSFR/sSFR and the H I gas fraction to show a mild correlation of Spearman's ρ = 0.30, indicating that star formation and disk growth are likely to proceed outward in galactic disks with high H I gas fractions. The H I gas fractions and ΔsSFR/sSFR of the galaxies also increase with the distance to the nearest L ⋆ neighbor, suggesting that galaxies are likely to sustain the cold gas in their interstellar medium and exhibit inside-out growth in isolated environments. However, the H I content in their circumgalactic medium (CGM), probed by the Lyα equivalent width (W Lyα ) excess, is observed to be suppressed in isolated environments, as is apparent from the strong anticorrelation between the W Lyα  excess and the distance to the fifth nearest L ⋆ neighbor (Spearman's ρ = -0.62). As expected, W Lyα  is also found to be suppressed in cluster galaxies. We find no relation between the W Lyα  excess of the detected CGM absorber and ΔsSFR/sSFR, implying that the enhancement and suppression of the circumgalactic H I gas does not affect the direction in which star formation proceeds in a galactic disk or vice versa.

Keywords: Disk galaxies, Spiral galaxies, H I line emission, Star formation, Interstellar medium, Circumgalactic medium
A Rest-frame Near-IR Study of Clumps in Galaxies at 1 &lt; z &lt; 2 Using JWST/NIRCam: Connection to Galaxy Bulges. A key question in galaxy evolution has been the importance of the apparent "clumpiness" of high-redshift galaxies. Until now, this property has been primarily investigated in rest-frame UV, limiting our understanding of their relevance. Are they short-lived or are they associated with more long-lived massive structures that are part of the underlying stellar disks? We use JWST/NIRCam imaging from the Cosmic Evolution and Epoch of Reionization Survey to explore the connection between the presence of these "clumps" in a galaxy and its overall stellar morphology, in a mass-complete ( $\mathrm{log}\,{M}_{* }/{M}_{\odot }\gt 10.0$ ) sample of galaxies at 1.0 &lt; z &lt; 2.0. Exploiting the uninterrupted access to rest-frame optical and near-IR light, we simultaneously map the clumps in galactic disks across our wavelength coverage, along with measuring the distribution of stars among their bulges and disks. First, we find that the clumps are not limited to the rest-frame UV and optical, but are also apparent in near-IR with ~60% spatial overlap. This rest-frame near-IR detection indicates that clumps would also feature in the stellar-mass distribution of the galaxy. A secondary consequence is that these will hence be expected to increase the dynamical friction within galactic disks leading to gas inflow. We find a strong negative correlation between how clumpy a galaxy is and strength of the bulge. This firmly suggests an evolutionary connection, either through clumps driving bulge growth or the bulge stabilizing the galaxy against clump formation, or a combination of the two. Finally, we find evidence of this correlation differing from rest-frame optical to near-IR, which could suggest a combination of varying formation modes for the clumps.

Keywords: Galaxy formation, Galaxy structure, Galaxy evolution
Multiline Stokes Synthesis of Ellerman Bombs: Obtaining Seamless Information from Photosphere to Chromosphere. Magnetic reconnection in the lower atmosphere is a critical process in determining the chromospheric dynamics, such as Ellerman bombs and UV bursts. Because the heating of the atmosphere significantly depends on the ionization degree and plasma β, which varies with height, it is essential to diagnose the height at which the magnetic reconnection takes place. Multiwavelength spectropolarimetry is a powerful solution to fulfill this requirement. We verify the diagnostic capabilities and usefulness of near-infrared multiwavelength spectropolarimetric observations for understanding magnetic reconnection phenomena by synthesizing the Stokes vector from a realistic magnetohydrodynamic simulation. The analysis considers two magnetic reconnection regions occurring at different heights. In the case of magnetic reconnection at low altitude, both red- and blueshifted components originating from reconnection bidirectional flow are identified in the photospheric lines, Fe I 8468 Å, K I 7664 Å, and K I 7698 Å. In the case of magnetic reconnection at high altitudes, chromospheric lines, Ca II 8498 Å and 8542 Å, show emission due to the heating that occurs at the upper part of the formation layer. These results suggest that multiwavelength spectropolarimetric observations are capable of distinguishing the height where magnetic reconnection occurs.

Keywords: Spectropolarimetry, Solar magnetic reconnection, Radiative magnetohydrodynamics, Solar photosphere, High altitude balloons, Solar physics, Solar magnetic fields, Radiative transfer, Solar chromosphere, Near infrared astronomy
Seasonal Thaws under Mid- to Low-pressure Atmospheres on Early Mars. Despite decades of scientific research on the subject, the climate of the first 1.5 Gyr of Mars' history has not been fully understood yet. Especially challenging is the need to reconcile the presence of liquid water for extended periods of time on the Martian surface with the comparatively low insolation received by the planet, a problem which is known as the Faint Young Sun paradox. In this paper, we use the Earth-like planet surface-temperature model (or ESTM), a latitudinal energy-balance model with enhanced prescriptions for meridional heat diffusion, and the radiative-transfer code EOS to investigate how seasonal variations of temperature can give rise to local conditions which are conducive to liquid-water runoffs. We include the effects of the Martian dichotomy, a northern ocean with either 150 or 550 m of global equivalent layer, and simplified CO2 or H2O clouds. We find that 1.3-2.0 bar CO2-dominated atmospheres can produce seasonal thaws due to inefficient heat redistribution, provided that the eccentricity and the obliquity of the planet are sufficiently different from zero. We also studied the impact of different values for the argument of perihelion. When local favorable conditions exist, they nearly always persist for &gt;15% of the Martian year. These results are obtained without the need for additional greenhouse gases (e.g., H2, CH4) or transient heat-injecting phenomena (e.g., asteroid impacts, volcanic eruptions). A moderate amount (0.1%-1%) of CH4 significantly widens the parameter space region in which seasonal thaws are possible.

Keywords: Mars, Planetary atmospheres, Computational methods, Astrobiology, Planetary climates
Black Hole Growth, Baryon Lifting, Star Formation, and IllustrisTNG. Quenching of star formation in the central galaxies of cosmological halos is thought to result from energy released as gas accretes onto a supermassive black hole. The same energy source also appears to lower the central density and raise the cooling time of baryonic atmospheres in massive halos, thereby limiting both star formation and black hole growth, by lifting the baryons in those halos to greater altitudes. One predicted signature of that feedback mechanism is a nearly linear relationship between the central black hole's mass (M BH) and the original binding energy of the halo's baryons. We present the increasingly strong observational evidence supporting a such a relationship, showing that it extends up to halos of mass M halo ~ 1014 M ⊙. We then compare current observational constraints on the M BH-M halo relation with numerical simulations, finding that black hole masses in IllustrisTNG appear to exceed those constraints at M halo &lt; 1013 M ⊙ and that black hole masses in EAGLE fall short of observations at M halo ~ 1014 M ⊙. A closer look at IllustrisTNG shows that quenching of star formation and suppression of black hole growth do indeed coincide with black hole energy input that lifts the halo's baryons. However, IllustrisTNG does not reproduce the observed M BH-M halo relation because its black holes gain mass primarily through accretion that does not contribute to baryon lifting. We suggest adjustments to some of the parameters in the IllustrisTNG feedback algorithm that may allow the resulting black hole masses to reflect the inherent links between black hole growth, baryon lifting, and star formation among the massive galaxies in those simulations.

Keywords: Supermassive black holes, Active galaxies, Galaxy evolution, Circumgalactic medium
Strong Carbon Features and a Red Early Color in the Underluminous Type Ia SN 2022xkq. We present optical, infrared, ultraviolet, and radio observations of SN 2022xkq, an underluminous fast-declining Type Ia supernova (SN Ia) in NGC 1784 (D ≈ 31 Mpc), from &lt;1 to 180 days after explosion. The high-cadence observations of SN 2022xkq, a photometrically transitional and spectroscopically 91bg-like SN Ia, cover the first days and weeks following explosion, which are critical to distinguishing between explosion scenarios. The early light curve of SN 2022xkq has a red early color and exhibits a flux excess that is more prominent in redder bands; this is the first time such a feature has been seen in a transitional/91bg-like SN Ia. We also present 92 optical and 19 near-infrared (NIR) spectra, beginning 0.4 days after explosion in the optical and 2.6 days after explosion in the NIR. SN 2022xkq exhibits a long-lived C I 1.0693 μm feature that persists until 5 days post-maximum. We also detect C II λ6580 in the pre-maximum optical spectra. These lines are evidence for unburnt carbon that is difficult to reconcile with the double detonation of a sub-Chandrasekhar mass white dwarf. No existing explosion model can fully explain the photometric and spectroscopic data set of SN 2022xkq, but the considerable breadth of the observations is ideal for furthering our understanding of the processes that produce faint SNe Ia.

Keywords: White dwarf stars, Type Ia supernovae, Supernovae
Velocity-space Signatures of Resonant Energy Transfer between Whistler Waves and Electrons in the Earth's Magnetosheath. Wave-particle interactions play a crucial role in transferring energy between electromagnetic fields and charged particles in space and astrophysical plasmas. Despite the prevalence of different electromagnetic waves in space, there is still a lack of understanding of fundamental aspects of wave-particle interactions, particularly in terms of energy flow and velocity-space characteristics. In this study, we combine a novel quasilinear model with observations from the Magnetospheric Multiscale mission to reveal the signatures of resonant interactions between electrons and whistler waves in magnetic holes, which are coherent structures often found in the Earth's magnetosheath. We investigate the energy transfer rates and velocity-space characteristics associated with Landau and cyclotron resonances between electrons and slightly oblique propagating whistler waves. In the case of our observed magnetic hole, the loss of electron kinetic energy primarily contributes to the growth of whistler waves through the n = -1 cyclotron resonance, where n is the order of the resonance expansion in linear Vlasov-Maxwell theory. The excitation of whistler waves leads to a reduction of the temperature anisotropy and parallel heating of the electrons. Our study offers a new and self-consistent understanding of resonant energy transfer in turbulent plasmas.

Keywords: Interplanetary turbulence, Space plasmas, Solar wind
Betatron Acceleration of Suprathermal Electrons Upstream of the Martian Bow Shock. Betatron acceleration, a plasma process obtaining particle energy in the perpendicular direction but reserving energy in the field-aligned direction, is the consequence of magnetic strength enhancement when the first adiabatic invariant is conserved. Such process has been widely reported in the terrestrial magnetosphere but is barely reported in other planetary environments. Here, based on the in situ measurements from the Mars Atmosphere and Volatile Evolution mission, we report two events of betatron acceleration upstream of the Martian bow shock. In both events, betatron accelerations increase the fluxes of suprathermal electrons. The acceleration processes in these events are quantitatively reproduced with an analytical model. Gratifyingly, we find the acceleration factors derived from the analytical model are well consistent with the observations of magnetic strength enhancement. These results for the first time show that the betatron acceleration is an active upstream of the Martian bow shock and is very useful to help us understand the generation of energetic electrons in the Martian environment.

Keywords: Space plasmas, Mars, Interplanetary particle acceleration, Planetary magnetospheres, Magnetic fields
Tidal Dissipation in Stably Stratified and Semiconvective Regions of Rotating Giant Planets: Incorporating Coriolis Forces. We study how stably stratified or semiconvective layers alter tidal dissipation rates associated with the generation of inertial, gravito-inertial, interfacial, and surface gravity waves in rotating giant planets. We explore scenarios in which stable (nonconvective) layers contribute to the high rates of tidal dissipation observed for Jupiter and Saturn in our solar system. Our model is an idealized spherical Boussinesq system incorporating Coriolis forces to study effects of stable stratification and semiconvective layers on tidal dissipation. Our detailed numerical calculations consider realistic tidal forcing and compute the resulting viscous and thermal dissipation rates. The presence of an extended stably stratified fluid core significantly enhances tidal wave excitation of both inertial waves (due to rotation) in the convective envelope and gravito-inertial waves in the dilute core. We show that a sufficiently strongly stratified fluid core enhances inertial wave dissipation in a convective envelope much like a solid core does. We demonstrate that efficient tidal dissipation rates (and associated tidal quality factors $Q^{\prime} $ )-sufficient to explain the observed migration rates of Saturn's moons-are predicted at the frequencies of the orbiting moons due to the excitation of inertial or gravito-inertial waves in our models with stable layers (without requiring resonance locking). Stable layers could also be important for tidal evolution of hot and warm Jupiters and hot Neptunes, providing efficient tidal circularization rates. Future work should study more sophisticated planetary models that also account for magnetism and differential rotation, as well as the interaction of inertial waves with turbulent convection.

Keywords: Internal waves, Solar system gas giant planets, Exoplanet tides, Tides, Astrophysical fluid dynamics, Extrasolar gaseous giant planets
CO Mapping of Cygnus-X-Volume Density Distribution. We present CO(2-1) and 13CO(2-1) maps of the Cygnus-X molecular cloud complex using the 10 m Heinrich Hertz Submillimeter Telescope. The maps cover the southern portion of the complex, which is strongly impacted by the feedback from the Cygnus OB2 association. Combining CO(1-0) and 13CO(1-0) maps from the Nobeyama 45 m Cygnus-X CO Survey, we carry out a multitransition molecular line analysis with RADEX and derive the volume density of velocity-coherent gas components. We select those components with a column density in the power-law tail part of the column density probability distribution function (N-PDF) and assemble their volume density into a volume density PDF (ρ-PDF). The ρ-PDF exhibits a power-law shape in the range of 104.5 cm-3 $\lesssim \,{n}_{{{\rm{H}}}_{2}}\,\lesssim $ 105.5 cm-3 with a fitted slope of α = -1.12 ± 0.05. The slope is shallower than what is predicted by simulations of rotationally supported structures or those undergoing gravitational collapse. Applying the same analysis to synthetic observations with feedback may help identify the cause of the shallow slope. The ρ-PDF provides another useful benchmark for testing models of molecular cloud formation and evolution.

Keywords: Stellar feedback, Molecular clouds, Photodissociation regions, Giant molecular clouds, Radiative transfer equation, Radiative transfer, Interstellar medium, Radiative transfer simulations