Sazuna/UAT_keywords huggingface dataset:
First Results for Solar Soft X-Ray Irradiance Measurements from the Third-generation Miniature X-Ray Solar Spectrometer. Three generations of the Miniature X-ray Solar Spectrometer (MinXSS) have flown on small satellites with the goal "to explore the energy distribution of soft X-ray (SXR) emissions from the quiescent Sun, active regions, and during solar flares, and to model the impact on Earth's ionosphere and thermosphere." The primary science instrument is the Amptek X123 X-ray spectrometer that has improved with each generation of the MinXSS experiment. This third-generation MinXSS-3 has a higher energy resolution and larger effective area than its predecessors and is also known as the Dual-zone Aperture X-ray Solar Spectrometer (DAXSS). It was launched on the INSPIRESat-1 satellite on 2022 February 14, and INSPIRESat-1 has successfully completed its 6 month prime mission. The INSPIRESat-1 is in a dawn-dusk, Sun-synchronous orbit and therefore has had 24 hr coverage of the Sun during most of its mission so far. The rise of Solar Cycle 25 has been observed by DAXSS. This paper introduces the INSPIRESat-1 DAXSS solar SXR observations, and we focus the science results here on a solar occultation experiment and multiple flares on 2022 April 24. One key flare result is that the reduction of elemental abundances appears greatest during the flare impulsive phase, thus highlighting the important role of chromospheric evaporation during flares to inject warmer plasma into the coronal loops. Furthermore, these results are suggestive that the amount of chromospheric evaporation is related to flare temperature and intensity.

Keywords: X-ray detectors, Solar x-ray emission, Solar flare spectra, Occultation, Solar corona
Mapping the Decline with Redshift of Dusty Star-forming Galaxies Using JWST and SCUBA-2. We use JWST NIRCam observations of the massive lensing cluster field A2744 to develop a red galaxy selection of f F444W &gt; 1 μJy and f F444W/f F150W &gt; 3.5 that picks out all nine &gt;4.5σ Atacama Large Millimeter/submillimeter Array 1.1 or 1.2 mm sources and 17 of the 19 &gt;5σ SCUBA-2 850 μm sources in the covered areas. We show that by using the red galaxies as priors, we can probe deeper in the SCUBA-2 850 μm image. This gives a sample of 44 &gt;3σ SCUBA-2 850 μm sources with accurate positions, photometric redshifts, and magnifications. To investigate why our red galaxy selection picks out the 850 μm sources, we next analyze an extended sample of 167 sources with f F444W &gt; 0.05 μJy and f F444W/f F150W &gt; 3.5. We find that the fainter f F444W sources in this sample are too faint to be detected in the SCUBA-2 850 μm image. We also show that there is a strong drop between z &lt; 4 and z &gt; 4 (a factor of around 5) in the ratio of the far-infrared luminosity estimated from the 850 μm flux to the ν ${L}_{\nu }^{d}$ (5000) at rest-frame 5000 Å. We argue that this result may be due to the high-redshift sources having less dust content than the lower-redshift sources.

Keywords: Starburst galaxies, Far infrared astronomy, Galaxy evolution, Near infrared astronomy
The Role of Mass and Environment on Satellite Distributions around Milky Way Analogs in the ROMULUS25 Simulation. We study satellite counts and quenched fractions for satellites of Milky Way analogs in ROMULUS25, a large-volume cosmological hydrodynamic simulation. Depending on the definition of a Milky Way analog, we have between 66 and 97 Milky Way analogs in ROMULUS25, a 25 Mpc per-side uniform volume simulation. We use these analogs to quantify the effect of environment and host properties on satellite populations. We find that the number of satellites hosted by a Milky Way analog increases predominantly with host stellar mass, while environment, as measured by the distance to a Milky Way-mass or larger halo, may have a notable impact in high isolation. Similarly, we find that the satellite quenched fraction for our analogs also increases with host stellar mass, and potentially in higher-density environments. These results are robust for analogs within 3 Mpc of another Milky Way-mass or larger halo, the environmental parameter space where the bulk of our sample resides. We place these results in the context of observations through comparisons to the Exploration of Local VolumE Satellites and Satellites Around Galactic Analogs surveys. Our results are robust to changes in Milky Way analog selection criteria, including those that mimic observations. Finally, as our samples naturally include Milky Way-Andromeda pairs, we examine quenched fractions in pairs versus isolated systems. We find potential evidence, though not conclusive, that pairs, defined as being within 1 Mpc of another Milky Way-mass or larger halo, may have higher satellite quenched fractions.

Keywords: Galaxy quenching, Dwarf galaxies, Galaxy evolution
XMM-Newton and INTEGRAL Observations of the Bright GRB 230307A: Vanishing of the Local Absorption and Limits on the Dust in the Magellanic Bridge. GRB 230307A is the second brightest gamma-ray burst detected in more than 50 years of observations and is located in the direction of the Magellanic Bridge. Despite its long duration, it is most likely the result of the merger of a compact binary ejected from a galaxy in the local universe (redshift z = 0.065). Our XMM-Newton observation of its afterglow at 4.5 days shows a power-law spectrum with photon index Γ = 1.73 ± 0.10, unabsorbed flux F 0.3-10 keV = (8.8 ± 0.5) × 10-14 erg cm-2 s-1, and no absorption in excess of that produced in our Galaxy and in the Magellanic Bridge. We derive a limit of ${N}_{{\rm{H}}}^{{\rm{HOST}}}\lt 5\times {10}^{20}$ cm-2 on the absorption at the GRB redshift, which is a factor ~5 below the value measured during the prompt phase. We searched for the presence of dust scattering rings with negative results and set an upper limit of the order of A  V  &lt; 0.05 on the absorption from dust in the Magellanic Bridge.

Keywords: Interstellar dust, Gamma-ray bursts, Magellanic Clouds
Estimating Ejecta Masses of Stripped-envelope Supernovae Using Late-time Light Curves. Stripped-envelope supernovae (SESNe) are a subclass of core-collapse supernovae that are deficient in hydrogen (SN IIb, SN Ib) and possibly helium (SN Ic) in their spectra. Their progenitors are likely stripped of this material through a combination of stellar winds and interactions with a close binary companion, but the exact ejecta mass range covered by each subtype and how it relates to the zero-age main-sequence progenitor mass is still unclear. Using a combination of semianalytic modeling and numerical simulations, we discuss how the properties of SESN progenitors can be constrained through different phases of the bolometric light curve. We find that the light-curve rise time is strongly impacted by the strength of radioactive nickel mixing and treatment of helium recombination. These can vary between events and are often not accounted for in simpler modeling approaches, leading to large uncertainties in ejecta masses inferred from the rise. Motivated by this, we focus on the late-time slope, which is determined by gamma-ray leakage. We calibrate the relationship between ejecta mass, explosion energy, and gamma-ray escape time T 0 using a suite of numerical models. Application of the fitting function we provide to bolometric light curves of SESNe should result in ejecta masses with approximately 20% uncertainty. With large samples of SESNe coming from current and upcoming surveys, our methods can be utilized to better understand the diversity and origin of the progenitor stars.

Keywords: Type Ib supernovae, Type Ic supernovae, Supernovae, Radiative transfer
VLTI/GRAVITY Observations and Characterization of the Brown Dwarf Companion HD 72946 B. Tension remains between the observed and modeled properties of substellar objects, but objects in binary orbits, with known dynamical masses, can provide a way forward. HD 72946 B is a recently imaged brown dwarf companion to a nearby, solar-type star. We achieve ~100 μas relative astrometry of HD 72946 B in the K band using VLTI/GRAVITY, unprecedented for a benchmark brown dwarf. We fit an ensemble of measurements of the orbit using orbitize! and derive a strong dynamical mass constraint M  B  = 69.5 ± 0.5 M Jup assuming a strong prior on the host star mass M  A  = 0.97 ± 0.01 M ☉ from an updated stellar analysis. We fit the spectrum of the companion to a grid of self-consistent BT-Settl-CIFIST model atmospheres, and perform atmospheric retrievals using petitRADTRANS. A dynamical mass prior only marginally influences the sampled distribution of effective temperature, but has a large influence on the surface gravity and radius, as expected. The dynamical mass alone does not strongly influence retrieved pressure-temperature or cloud parameters within our current retrieval setup. Independently of the cloud prescription and prior assumptions, we find agreement within ±2σ between the C/O of the host (0.52 ± 0.05) and brown dwarf (0.43-0.63), as expected from a molecular cloud collapse formation scenario, but our retrieved metallicities are implausibly high (0.6-0.8) in light of the excellent agreement of the data with the solar-abundance model grid. Future work on our retrieval framework will seek to resolve this tension. Additional study of low surface gravity objects is necessary to assess the influence of a dynamical mass prior on atmospheric analysis.

Keywords: Optical interferometry, Brown dwarfs, L dwarfs, Long baseline interferometry, Stellar atmospheres, Orbit determination, Exoplanet atmospheres, Interferometry
Collapse of Rotating Massive Stars Leading to Black Hole Formation and Energetic Supernovae. We explore a possible explosion scenario resulting from core collapses of rotating massive stars that leave a black hole by performing radiation-viscous-hydrodynamics simulations in numerical relativity. We take moderately and rapidly rotating compact pre-collapse stellar models with zero-age main-sequence masses of 9M ⊙ and 20M ⊙ based on stellar evolution calculations as the initial conditions. We find that viscous heating in the disk formed around the central black hole is the power source for an outflow. The moderately rotating models predict a small ejecta mass of the order of 0.1M ⊙ and an explosion energy of ≲1051 erg. Due to the small ejecta mass, these models may predict a short-timescale transient with a rise time of 3-5 days. This can lead to a bright (~1044 erg s-1) transient, like superluminous supernovae in the presence of a dense massive circumstellar medium. For hypothetically rapidly rotating models that have a high mass-infall rate onto the disk, the explosion energy is ≳3 × 1051 erg, which is comparable to or larger than that of typical stripped-envelope supernovae, indicating that a fraction of such supernovae may be explosions powered by black hole accretion disks. The explosion energy is still increasing at the end of the simulations with a rate of &gt;1050 erg s-1, and thus, it may reach ~1052 erg. A nucleosynthesis calculation shows that the mass of 56Ni amounts to ≳0.1M ⊙, which, together with the high explosion energy, may satisfy the required amount for broad-lined type Ic supernovae. Irrespective of the models, the lowest value of the electron fraction of the ejecta is ≳0.4; thus, synthesis of heavy r-process elements is not found in our models.

Keywords: Burst astrophysics, Ejecta, Core-collapse supernovae, High energy astrophysics
Fermi Constraints on the Ejecta Speed and Prompt Emission Region of the Distant GRB 220101A. At redshift z = 4.618, GRB 220101A is the most distant gamma-ray burst (GRB) detected by Fermi/LAT to date. It is also a very energetic event, with an equivalent isotropic energy of 3.6 × 1054 erg. We jointly analyzed the Fermi/GBM and LAT observations of GRB 220101A with two independent approaches and found a significant spectral break at sub-100 MeV energies during the prompt emission. The fast variability of the emission suggests that this spectral attenuation is caused by internal opacity to pair creation. Regardless of the nature of the emission processes assumed in the spectral analysis, we infer a moderate value for the jet Lorentz factor, Γ ~ 110, and find that all of the high-energy emission was produced above and near the photosphere, at a distance of ~1014 cm from the central engine. We compare these results with the four other LAT-detected GRBs with similar properties.

Keywords: Gamma-ray bursts, High energy astrophysics
Twenty-five Years of Accretion onto the Classical T Tauri Star TW Hya. Accretion plays a central role in the physics that governs the evolution and dispersal of protoplanetary disks. The primary goal of this paper is to analyze the stability over time of the mass accretion rate onto TW Hya, the nearest accreting solar-mass young star. We measure veiling across the optical spectrum in 1169 archival high-resolution spectra of TW Hya, obtained from 1998-2022. The veiling is then converted to accretion rate using 26 flux-calibrated spectra that cover the Balmer jump. The accretion rate measured from the excess continuum has an average of 2.51 × 10-9 M ☉ yr-1 and a Gaussian distribution with an FWHM of 0.22 dex. This accretion rate may be underestimated by a factor of up to 1.5 because of uncertainty in the bolometric correction and another factor of 1.7 because of excluding the fraction of accretion energy that escapes in lines, especially Lyα. The accretion luminosities are well correlated with He line luminosities but poorly correlated with Hα and Hβ luminosity. The accretion rate is always flickering over hours but on longer timescales has been stable over 25 years. This level of variability is consistent with previous measurements for most, but not all, accreting young stars.

Keywords: High resolution spectroscopy, Classical T Tauri stars, Protoplanetary disks, Variable stars, Stellar accretion disks
MAPS: Constraining Serendipitous Time Variability in Protoplanetary Disk Molecular Ion Emission. Theoretical models and observations suggest that the abundances of molecular ions in protoplanetary disks should be highly sensitive to the variable ionization conditions set by the young central star. We present a search for temporal flux variability of HCO+ J = 1-0, which was observed as a part of the Molecules with Atacama Large Millimeter/submillimeter Array (ALMA) at Planet-forming Scales ALMA Large Program. We split out and imaged the line and continuum data for each individual day the five sources were observed (HD 163296, AS 209, GM Aur, MWC 480, and IM Lup, with between three and six unique visits per source). Significant enhancement (&gt;3σ) was not observed, but we find variations in the spectral profiles in all five disks. Variations in AS 209, GM Aur, and HD 163296 are tentatively attributed to variations in HCO+ flux, while variations in IM Lup and MWC 480 are most likely introduced by differences in the uv coverage, which impact the amount of recovered flux during imaging. The tentative detections and low degree of variability are consistent with expectations of X-ray flare-driven HCO+ variability, which requires relatively large flares to enhance the HCO+ rotational emission at significant (&gt;20%) levels. These findings also demonstrate the need for dedicated monitoring campaigns with high signal-to-noise ratios to fully characterize X-ray flare-driven chemistry.

Keywords: Radio spectroscopy, Stellar x-ray flares, Astrochemistry, Young stellar objects, Pre-main sequence stars, Stellar flares, Protoplanetary disks, Radio astronomy
AMUSE-Antlia. I. Nuclear X-Ray Properties of Early-type Galaxies in a Dynamically Young Galaxy Cluster. To understand the formation and growth of supermassive black holes (SMBHs) and their coevolution with host galaxies, it is essential to know the impact of environment on the activity of active galactic nuclei (AGNs). We present new Chandra X-ray observations of nuclear emission from member galaxies in the Antlia cluster, the nearest non-cool core and the nearest merging galaxy cluster, residing at D = 35.2 Mpc. Its inner region, centered on two dominant galaxies NGC 3268 and NGC 3258, has been mapped with three deep Chandra ACIS-I pointings. Nuclear X-ray sources are detected in 7/84 (8.3%) early-type galaxies (ETG) and 2/8 (25%) late-type galaxies with a median detection limit of 8 × 1038 erg s-1. All nuclear X-ray sources but one have a corresponding radio continuum source detected by MeerKAT at the L band. Nuclear X-ray sources detected in early-type galaxies are considered the genuine X-ray counterpart of low-luminosity AGN. When restricted to a detection limit of $\mathrm{log}({L}_{{\rm{X}}}/\mathrm{erg}\,{{\rm{s}}}^{-1})\geqslant 38.9$ and a stellar mass of $10\leqslant \mathrm{log}({M}_{\star }/{M}_{\odot })\lt 11.6$ , six of 11 ETGs are found to contain an X-ray AGN in Antlia, exceeding the AGN occupation fraction of 7/39 (18.0%) and 2/12 (16.7%) in the more relaxed, cool core clusters, Virgo and Fornax, respectively, and rivaling that of the AMUSE-Field ETG of 27/49 (55.1%). Furthermore, more than half of the X-ray AGN in Antlia is hosted by its younger subcluster, centered on NGC 3258. We believe that this is because SMBH activity is enhanced in a dynamically young cluster compared to relatively relaxed clusters.

Keywords: Low-luminosity active galactic nuclei, X-ray active galactic nuclei
Phase-space Analysis of Ordered and Disordered Nonthermal Ion Energization during Magnetic Reconnection. Anomalous ion heating is frequently observed to accompany magnetic reconnection, yet there is little consensus on its origin. Instead of the usual velocity-space analysis, we use phase-space analysis to exhaustively explain how ions are nonthermally energized during collisionless, antiparallel magnetic reconnection. There are both ordered and disordered aspects in the process; the former is explained in terms of conservative quantities, and the latter is explained by demonstrating chaos through a direct calculation of Lyapunov exponents. The former induces "multibeam-like heating" in all three directions, whereas the latter induces stochastic bulk heating. Profiles of the ion temperature tensor components during reconnection can be easily understood by the phase-space distributions of ions in different motional stages.

Keywords: Solar coronal heating, Solar magnetic reconnection
Radiative Magnetohydrodynamic Simulation of the Confined Eruption of a Magnetic Flux Rope: Unveiling the Driving and Constraining Forces. We analyze the forces that control the dynamic evolution of a flux rope eruption in a three-dimensional radiative magnetohydrodynamic simulation. The confined eruption of the flux rope gives rise to a C8.5 flare. The flux rope rises slowly with an almost constant velocity of a few kilometers per second in the early stage when the gravity and Lorentz force are nearly counterbalanced. After the flux rope rises to the height at which the decay index of the external poloidal field satisfies the torus instability criterion, the significantly enhanced Lorentz force breaks the force balance and drives the rapid acceleration of the flux rope. Fast magnetic reconnection is immediately induced within the current sheet under the erupting flux rope, which provides strong positive feedback to the eruption. The eruption is eventually confined due to the tension force from the strong external toroidal field. Our results suggest that the gravity of plasma plays an important role in sustaining the quasi-static evolution of the preeruptive flux rope. The Lorentz force, which is contributed from both the ideal magnetohydrodynamic instability and magnetic reconnection, dominates the dynamic evolution during the eruption process.

Keywords: Solar active region magnetic fields, Solar flares, Radiative magnetohydrodynamics, Solar magnetic fields, Solar activity
Variability of Interplanetary Shock and Associated Energetic Particle Properties as a Function of the Time Window Around the Shock. We study the effect of sampling windows on derived shock and associated energetic storm particle (ESP) properties in 296 fast-forward interplanetary shocks using Advanced Composition Explorer measurements at 1 au between 1998 February and 2013 August. We vary the time windows from 2 minutes to 20 minutes for the shock properties and from 2 minutes to 540 minutes for ESP properties. Variability is quantified by the median absolute deviation statistic. We find that the magnetic, density, and temperature compression ratios vary from their median values by 17.03%, 20.05%, and 25.91%, respectively; shock speed by 16.26%; speed jump by 45.46%; Alfvénic Mach number by 31.53%; and shock obliquity by 24.25%. Spectral indices in the 2 minute-540 minute windows downstream of the shock vary from the median value of 1.79 by 26.05% and by 30.53% from the 1.70 median value upstream of the shock. Similarity of ESP spectral indices upstream and downstream of the shock suggest that these ESP populations are likely locally accelerated at the shock. Furthermore, we find that for a moving sampling window around the shock, values for the density ratio hold for ~10 minutes; the magnetic ratio and shock speed jump hold for ~30 minutes and ~60 minutes, respectively. Fixing the upstream window to 2 minutes and moving only in the downstream direction, the density ratio holds for ~60 minutes downstream, magnetic ratio holds for ~30 minutes, and the shock speed jump holds for ~110 minutes. Beyond these time windows, derived shock properties are no longer representative of shock properties. These results provide constraints for modeling and forecasting efforts of shock and ESP-associated properties.

Keywords: Interplanetary shocks, Solar energetic particles, Timing variation methods, Interplanetary particle acceleration, Solar coronal mass ejections
Four Years of Type Ia Supernovae Observed by TESS: Early-time Light-curve Shapes and Constraints on Companion Interaction Models. We present 307 type Ia supernova (SN) light curves from the first 4 yr of the Transiting Exoplanet Survey Satellite mission. We use this sample to characterize the shapes of the early-time light curves, measure the rise times from first light to peak, and search for companion star interactions. Using simulations, we show that light curves must have noise &lt;10% of the peak flux to avoid biases in the early-time light-curve shape, restricting our quantitative analysis to 74 light curves. We find that the mean power-law index ${t}^{{\beta }_{1}}$ of the early-time light curves is β 1 = 1.93 ± 0.57, and the mean rise time to peak is 15.7 ± 3.5 days. The underlying population distribution for β 1 may instead consist of a Gaussian component with mean 2.29, width 0.34, and a long tail extending to values less than 1.0. We find that the data can rarely distinguish between models with and without companion interaction models. Nevertheless, we find three high-quality light curves that tentatively prefer the addition of a companion interaction model, but the statistical evidence for the companion interactions is not robust. We also find two SNe that disfavor the addition of a companion interaction model to a curved power-law model. Taking the 74 SNe together, we calculate 3σ upper limits on the presence of companion signatures to control for orientation effects that can hide companions in individual light curves. Our results rule out common progenitor systems with companions having Roche lobe radii &gt;31 R ☉ (separations &gt;5.7 × 1012 cm, 99.9% confidence level) and disfavor companions having Roche lobe radii &gt;10 R ☉ (separations &gt;1.9 × 1012 cm, 95% confidence level). Lastly, we discuss the implications of our results for the intrinsic fraction of single degenerate progenitor systems.

Keywords: Type Ia supernovae