Sazuna/UAT_keywords huggingface dataset:
The Origin of Energetic Solar Protons: Comparative Analysis of Ground-level Enhancement (GLE) Events and Non-GLE Solar Energetic Particle Events. This study explores the acceleration origins of solar energetic particles (SEPs) by analyzing the energy spectral characteristics of particles in ground-level enhancement (GLE) events and common SEP (non-GLE) events, as well as the correlations of the peak intensities of energetic particles with flare and coronal mass ejection (CME) diagnostic parameters. By examining the peak energy spectra of protons, for protons with energies &gt;66 MeV, the peak intensities in most GLE events are significantly higher than those in SEP events, establishing an energy threshold distinguishing GLE from non-GLE events. Given the strong correlation between energetic electrons and protons, radio bursts and soft X-rays (SXRs) produced by energetic electrons can be used to study acceleration regions of GLE. Based on data from solar cycles 23 and 24, multifrequency radio data (5, 8.8, and 15.4 GHz) and SXR intensity analysis reveal the heights of particle acceleration. The results indicate that protons with energies &gt;66 MeV in GLE events are closely associated with flare-related acceleration in the low corona, although a contribution from CME-driven shock acceleration cannot be excluded. In contrast, lower-energy protons (&lt;10 MeV) are primarily accelerated by CME-driven shocks. Moreover, SEPs at intermediate energies exhibit a mixed origin, which includes particles accelerated by both flares and CME-driven shocks. These findings provide key insights into the mechanisms of particle acceleration in solar events.

Keywords: Solar flares, Solar energetic particles, Solar coronal mass ejection shocks, Solar coronal mass ejections, Solar activity
FIELDMAPS Data Release: Far-infrared Polarization in the "Bones" of the Milky Way. Polarization observations of the Milky Way and many other spiral galaxies have found a close correspondence between the orientation of spiral arms and magnetic field lines on scales of hundreds of parsecs. This paper presents polarization measurements at 214 μm toward 10 filamentary candidate "bones" in the Milky Way using the High-resolution Airborne Wide-band Camera on the Stratospheric Observatory for Infrared Astronomy. These data were taken as part of the Filaments Extremely Long and Dark: A Magnetic Polarization Survey and represent the first study to resolve the magnetic field in spiral arms at parsec scales. We describe the complex yet well-defined polarization structure of all 10 candidate bones, and we find a mean difference and standard deviation of −74° ± 32° between their filament axis and the plane-of-sky magnetic field, closer to a field perpendicular to their length rather than parallel. By contrast, the 850 μm polarization data from Planck on scales greater than 10 pc show a nearly parallel mean difference of 3° ± 21°. These findings provide further evidence that magnetic fields can change orientation at the scale of dense molecular clouds, even along spiral arms. Finally, we use a power law to fit the dust polarization fraction as a function of total intensity on a cloud-by-cloud basis and find indices between −0.6 and −0.9, with a mean and standard deviation of −0.7 ± 0.1. The polarization, dust temperature, and column density data presented in this work are publicly available online.

Keywords: Interstellar filaments, Milky Way magnetic fields, Far infrared astronomy, Dust continuum emission, Star formation, Polarimetry
CANUCS/Technicolor Data Release 1: Imaging, Photometry, Slit Spectroscopy, and Stellar Population Parameters. We present the first data release of the Canadian NIRISS Unbiased Cluster Survey (CANUCS), a JWST Cycle 1 GTO program targeting five lensing clusters and flanking fields in parallel (A370, MACS0416, MACS0417, MACS1149, and MACS1423; survey area ∼100 arcmin2), with NIRCam imaging, NIRISS slitless spectroscopy, and NIRSpec prism multiobject spectroscopy. Fields centered on cluster cores include imaging in eight bands from 0.9─4.4 μm, alongside continuous NIRISS coverage from 1.15─2 μm, while the NIRCam flanking fields provide five wide-band and nine medium-band filters for exceptional spectral sampling, all to ∼29 magAB. We also present JWST in Technicolor, a Cycle 2 follow-up GO program targeting three CANUCS clusters (A370, MACS0416, and MACS1149). The Technicolor program adds NIRISS slitless spectroscopy in F090W to the cluster fields while adding eight wide-, medium-, and narrowband filters to the flanking fields. This provides NIRCam imaging in all wide- and medium-band filters over ∼30 arcmin2. This paper describes our data reduction and photometry methodology. We release NIRCam, NIRISS, and Hubble Space Telescope imaging, point-spread functions (PSFs), PSF-matched imaging, photometric catalogs, and photometric and spectroscopic redshifts. We provide lens models and stellar population parameters in up to 19 filters for ∼53,000 galaxies in the cluster fields, and ∼44,000 galaxies in up to 29 filters in the flanking fields. We further present 733 NIRSpec spectra and redshift measurements up to z = 10.8. Comparing against our photometric redshifts, we find catastrophic outlier rates of only 4%─7% and scatter of σNMAD of 0.01─0.03. *The public release of the CANUCS dataset is dedicated to the memory of John Hutchings, whose decades of work enabled Canada's involvement in JWST and the creation of this dataset.

Keywords: Galaxy clusters, Sky surveys, Galaxy evolution, Photometry, Spectroscopy
Multiscale Magnetic Reconnection in the Genesis of Young Slow Solar Wind. The genesis of solar wind remains elusive due to limited multi-instrument observations of its source regions. Here, we introduce a novel "see and touch" technique, integrating remote-sensing observations with in situ measurements from Parker Solar Probe (PSP). This approach allows us to obtain 3D trajectories of flow structures such as streamer blobs and explore their in situ properties. With this approach, we link blobs observed by remote sensing and high-density jets (HDJs) measured in situ. The blobs are embedded in streamer rays, while the HDJs are found when PSP crosses the heliospheric current sheet (HCS). Our findings suggest that large-scale blobs/HDJs originate from primary reconnection in the near-Sun HCS, while secondary reconnection in smaller-scale current sheets forms multiple flux ropes, which merge to trigger further small-scale reconnection. Detailed in situ analysis reveals that turbulent magnetic reconnection is a key mechanism for dissipating filamentary HCS and energizing plasmas in blobs/HDJs. The multiscale magnetic reconnection accelerates the proton core population and mixes it with the beam population, driving bulk acceleration and heating of the nascent slow solar wind.

Keywords: Solar wind, Solar magnetic reconnection, Heliosphere
Measurements of Cosmic Proton Flux through Neutron Monitors Using Deep Networks and Imputation Techniques in the AMS-02 Era. Accurate measurements of cosmic proton flux are essential for studying the modulation processes of cosmic rays during the solar activity cycle. A proton flux measurement method, based on ground-based neutron monitor (NM) data and deep learning techniques, is presented. After the necessary preprocessing of ground-based NM data using a convolutional neural network model, we model the relationship between NM observations and proton flux measured by the Alpha Magnetic Spectrometer (AMS). The daily cosmic proton flux, ranging from 1 to 100 GV, is obtained for the period from 2011 to 2024 and shows strong agreement with the observed values. In addition, daily proton flux is computed for periods when AMS measurements were unavailable for operational reasons. For the first time, hourly proton flux as a function of rigidity is calculated for the study of short-time solar activity.

Keywords: Convolutional neural networks, Forbush effect, Time series analysis, Cosmic rays
COSMOS Spectroscopic Redshift Compilation (First Data Release): 488,000 Redshifts Encompassing Two Decades of Spectroscopy. We present the COSMOS Spectroscopic Redshift Compilation encompassing ∼20 yr of spectroscopic redshifts within a 10 deg2 area centered on the 2 deg2 COSMOS legacy field. This compilation contains 487,666 redshifts of 266,284 unique objects from 138 individual programs up to z ∼ 8 with median stellar mass ∼108.4─1010 M⊙ (redshift dependent). Rest-frame NUVrJ colors and star formation rate─stellar mass correlations show that the compilation primarily contains low-to-intermediate-mass star-forming and massive, quiescent galaxies at z &lt; 1.25 and mostly low-mass bursty star-forming galaxies at z &gt; 2. Sources in the compilation cover a diverse range of environments, including protoclusters such as "Hyperion." The full compilation is 50% spectroscopically complete by i ∼ 23.4 mag and Ks ∼ 21.6 mag; however, this is redshift dependent. Spatially, the compilation is &gt;50% (&gt;30%) complete within the central (outer) region limited to i &lt; 24 mag and Ks &lt; 22.5 mag, separately. We demonstrate how the compilation can be used to validate photometric redshifts and investigate calibration metrics. By training self-organizing maps on COSMOS2020/Classic and projecting the compilation onto it, we find key subpopulations currently lacking spectroscopic coverage, including z &lt; 1 intermediate-mass quiescent and low-/intermediate-mass bursty star-forming galaxies, z ∼ 2 massive quiescent galaxies, and z &gt; 3 massive star-forming galaxies. This highlights how combining self-organizing maps with our compilation can provide guidance for future spectroscopic observations to get a complete spectroscopic view of galaxy populations. Lastly, the compilation will undergo periodic data releases incorporating new spectroscopic redshifts and providing a lasting legacy resource for the community.

Keywords: Galaxy formation, Galaxy evolution, Galaxy spectroscopy, Redshift surveys, Catalogs
The NASA Ames PAH IR Spectroscopic Database: Computational Version 4.00, Software Tools, Website, and Documentation. Version 4.00 of the library of computed spectra of the NASA Ames PAH IR Spectroscopic Database (PAHdb) includes an expanded set of polycyclic aromatic hydrocarbon (PAH) spectra, totaling 10,749, calculated using the harmonic approximation and a basis set containing polarization functions. The software tools offered through PAHdb have also been significantly expanded, including optimizations to more efficiently handle the large number of spectra now available. Major improvements have been made to the PAHdb website, which now also offers new libraries of laboratory and computed PAH cluster spectra. PAH boundary-edge codes are now being used throughout PAHdb to hold structural information and to search for specific PAH isomers. All enhancements and updates are described in expanded documentation. As a demonstration, the updated version 4.00 computational library and improved software tools are used to analyze the James Webb Space Telescope spectrum of the atomic photodissociation region of the Orion Bar and show a remarkable improvement in matching the 6.2 μm emission band and the 10─15 μm emission over earlier library versions.

Keywords: Astronomy databases
Recalibration of the Landolt UBVRI Standard Stars and the Generation of 5.4 Million New UBVRI Standard Stars Using LAMOST and Gaia. We present an independent validation and recalibration of the Landolt 2013 (celestial equator and δ ∼ −50∘) and 2016 (δ ∼ −50∘) standard stars in the Johnson UBV and Kron─Cousins RI systems, using tens of thousands of XP spectra-based synthetic photometry (XPSP) data from the BEst STar (BEST) database. Our analysis reveals an overall zero-point offset between the 2016 and 2013 datasets. We further identify zero-point offsets for each standard field, ranging from 5 to 14 mmag across all UBVRI bands, with correlations between offsets in different bands. Additionally, we confirm the spatial structures up to 7─10 mmag in the BVRI bands. We also find that spatial structures are similar across bands for the same field, and similar across different fields for the same band. These similarities may arise from the averaged flat fields from each observing run. The recalibrated results are consistent with the XPSP data within 48 mmag in the U band, 11 mmag in the B band, and 5─6 mmag in the VRI bands in the brightness G &lt; 16. Furthermore, based on stellar atmospheric parameters from LAMOST DR12 and Gaia DR3 photometry, along with the XPSP data, we derive temperature- and extinction-dependent extinction coefficients for the UBVRI bands as well as a LAMOST- and Gaia-based catalog of 5.4 million standard stars in the UBVRI bands, for which the U-band photometry of the vast majority of sources exhibits significantly higher precision than XPSP. The recalibrated Landolt standard stars and LAMOST- and Gaia-based standard stars will be available on the BEST website (https://nadc.china-vo.org/data/best/) and on Zenodo at doi:10.12149/101704.

Keywords: Stellar photometry, Calibration, Extinction
A Photometric Survey of over 200 V-type Asteroids and Their Phase-curve Analysis. V-type asteroids are considered to be crustal fragments of asteroid (4) Vesta and possibly of other differentiated parent bodies that once existed in the main asteroid belt. A dedicated photometric survey of 213 V-type asteroids and V-type candidates is presented, based on unfiltered CCD observations roughly calibrated with stars from the Carlsberg Meridian Catalogue. The rotation properties and phase-curve slope parameters (G) were derived for most of the targets. Additional phase-curve parameters (G12, G1, and G2) were determined for selected apparitions, and approximate empirical relationships between G and the indexed phase-curve parameters were established. The median and mean values of these parameters, together with the standard deviations, can provide practical approximations for V-type asteroids with poorly determined parameters. Contamination of the sample by a few asteroids of a different taxonomic type is not ruled out, but is expected to have a negligible effect on the result. A comparison between V-types within the Vesta family and the overall sample indicates subtle but systematic differences in phase-curve parameters. A weak correlation between phase-curve parameters and orbital distance from (4) Vesta is tentatively found within the family. As the internal magnitude level is close to the Cousins R band, absolute magnitudes HR can be estimated for the entire dataset, with a typical uncertainty of approximately 0.2 mag, especially for their mean values from multiple apparitions.

Keywords: Asteroid satellites, CCD photometry, Asteroid rotation, Asteroids
200,000+ Deep Learning─inferred Periods of Stellar Variability from the All-Sky Automated Survey for Supernovae. Stars exhibit a range of variability periods that depend on their mass, age, and evolutionary stage. For space-based photometric data, convolutional neural networks (CNNs) have demonstrated success in recovering and measuring periodic variability from photometric missions like Kepler and TESS. All-sky ground-based surveys can have similar if not longer baselines than space-based missions; however, these datasets are more challenging to work with due to irregular sampling, more complex systematics, and larger data gaps. In this work, we demonstrate that CNNs can be used to derive variability periods from ground-based surveys. From the All-Sky Automated Survey for Supernovae, we recover 208,260 variability periods between 1 and 30 days, approximately 60% of which are new detections. We recover periods for active RSCVn, anomalous sub-subgiants, and cool dwarfs that are consistent with previously measured rotation periods, while periods for stars above the Kraft break are generally spurious. We also identify periodic signals in tens of thousands of giant stars that correspond to frequencies of stellar oscillations rather than rotation. Our results highlight that CNNs can be used on sparsely sampled ground-based photometry to recover periodicity. We conclude that the findings of our work are very promising for the potential recovery of hundreds of thousands of stellar rotation periods in data from the Vera C. Rubin Observatory's Legacy Survey of Space and Time and the Nancy Grace Roman Space Telescope's Galactic Bulge Time Domain Survey.

Keywords: Light curves, Convolutional neural networks, Irregular cadence, Stellar rotation, Time series analysis
The CAI Database: <SUP>26</SUP>Al─<SUP>26</SUP>Mg Isotope Systematics. We present a publicly available calcium─aluminum-rich inclusion (CAI) database that focuses on the initial 26Al/27Al0 ratio in CAIs, designed in a way that researchers in cosmochemistry and astrophysics may find useful. To date, the database contains 497 CAIs from 75 peer-reviewed papers. The CAIs are from all chondrite groups and cover different CAI types, textures, and sizes. The database includes the paper; the host meteorite; the CAI name and type; the 26Al/27Al0,  δ26Mg0∗ , and δ25Mg values and their uncertainties; the number of regression points; the maximum 27Al/24Mg; the mean-squared weighted deviation; the CAI size; and CAI descriptions. We grouped the CAIs in different ways to discuss 26Al/27Al0 ratio distributions with implications for the CAI formation timeline. Overall, we agree with previous authors that CAIs have a bimodal 26Al distribution: CAIs with robust isochrons (n = 151) have a median 26Al/27Al0 = 4.8 × 10−5 (with a 1σ standard error of 0.1), while those with isotopic anomalies (n = 87) have a median 26Al/27Al0 = 0.3 × 10−5 (with a 1σ standard error of 0.2). However, the large standard deviation of both groups (1.3 and 2.3, respectively) indicates that the 26Al/27Al0 values scatter significantly within each population. CAI types and groups can have distinct 26Al/27Al0 and  δ26Mg0∗ , but the unmelted inclusions (n = 33) have the highest median 26Al/27Al0 = 5.1 × 10−5 and a low median  δ26Mg0∗  = −0.05‰. We find slightly different 26Al/27Al0 distributions between CAI chondrite types, but no differences between petrographic types or sizes. These observations can help us to understand CAI formation in the context of astrophysical models.

Keywords: Isotopic abundances, Cosmochemistry, Solar system, Protoplanetary disks, Cosmochronology
Planar Collisionless Shock Simulations with the Semi-implicit Particle-in-cell Model FLEKS. This study investigates the applicability of the semi-implicit particle-in-cell code FLexible Exascale Kinetic Simulator (FLEKS) to heliospheric shock simulations. We examine one- and two-dimensional local planar shock simulations, initialized using MHD states with upstream conditions representative of plasmas in the hypersonic, β ∼ 1 regime, for both quasi-perpendicular and quasi-parallel configurations. The refined algorithm in FLEKS proves robust, enabling accurate shock simulations with a grid resolution on the order of the electron inertial length de. Our simulations successfully capture key shock features, including shock structures (foot, ramp, overshoot, and undershoot), upstream and downstream waves (fast magnetosonic, whistler, Alfvén ion-cyclotron, and mirror modes), and non-Maxwellian particle distributions. Crucially, we find that at least two spatial dimensions are critical for accurately reproducing downstream-wave physics in quasi-perpendicular shocks and capturing the complex dynamics of quasi-parallel shocks, including surface rippling, shocklets, short, large-amplitude magnetic structures, magnetic reconnection, and jets. Furthermore, our parameter studies demonstrate the impact of mass ratio and grid resolution on shock physics. This work provides valuable guidance for selecting appropriate physical and numerical parameters for shock simulations using a semi-implicit PIC method, paving the way for incorporating kinetic shock processes into large-scale collisionless plasma simulations with the MHD-AEPIC model.

Keywords: Space plasmas, Shocks, Plasma astrophysics
A Systematic Search for Active Galactic Nucleus Flares in ZTF Data Release 23. Active galactic nuclei (AGNs) are known to exhibit stochastic variability across a wide range of timescales and wavelengths. AGN flares are extreme outbursts that deviate from this typical behavior and may trace a range of energetic physical processes. Using 6 yr of data from Zwicky Transient Facility Data Release 23, we conduct a systematic search for AGN flares among a sample of well-sampled AGNs and AGN candidates. We construct two catalogs: the AGN Flare Coarse Catalog, containing 28,504 flares identified via Bayesian blocks and Gaussian processes, and the AGN Flare Refined Catalog, comprising 1984 high-confidence flares selected using stricter criteria. We analyze their spatial distribution, temporal characteristics, host-AGN type, and potential origins. Some flares can be associated with known supernovae, tidal disruption events, or blazars, and a few may be linked to binary black hole mergers or microlensing events. These catalogs provide a valuable resource for studying transient phenomena in AGNs and are publicly available in the online machine-readable table and on GitHub.

Keywords: Active galactic nuclei, Quasars
Highly Efficient Identification of Extreme Emission-line Galaxies in the Local Universe: &gt;8000 New Green Pea Candidates at 0.12 &lt; z &lt; 0.36. The currently known compact extreme emission-line galaxies (the "Green Peas" (GPs)) in the Sloan Digital Sky Survey (SDSS) are rare and were mostly found among serendipitous spectroscopic targets, thus leaving open the possibility that a substantial population of GPs is missed. A significantly larger number of identified GPs in the Local Universe might provide a better characterization of their high-redshift analogs and Lyman continuum escape. In this paper, we confront the challenges of robustly identifying GPs without spectroscopic information, a needed approach considering the incompleteness of spectroscopic surveys for compact sources. The principal difficulty stems from a significant contamination of photometric candidates by stars and quasars of similar color. To solve this, we introduce a spectral energy distribution matching method, which separates candidate GPs from contaminants on the basis of SDSS and Wide-field Infrared Survey Explorer photometry of spectroscopically confirmed stars, quasars, and galaxies. The method has an effectiveness of 85% and a contamination rate of ∼10%. With it, we identify ∼9600 GP candidates expected to lie in the 0.12 &lt; z &lt; 0.36 range—a tenfold increase over what would be selected using SDSS DR18 spectra. Some of the new GPs are as bright as r ∼ 19, and 1200 are predicted to have [O III]5007 equivalent widths in excess of 500 Å. The new population contains many "Extended Peas," which are absent among known GPs and possibly represent merging systems. We provide catalogs containing 8313 newly identified GP candidates, as well as 917 GPs confirmed using SDSS spectroscopy and 521 GPs with spectroscopic redshifts from LAMOST and other sources.

Keywords: Emission line galaxies