Sazuna/UAT_keywords huggingface dataset:
A Systematic Magnetic Polarity Inversion Line Data Set from SDO/HMI Magnetograms. Magnetic polarity inversion lines (PILs) detected in solar active regions have long been recognized as arguably the most essential feature for triggering instabilities such as flares and eruptive events (i.e., eruptive flares and coronal mass ejections). In recent years, efforts have been focused on using features engineered from PILs for solar eruption prediction. However, PIL rasters and metadata are often generated as by-products and are not accessible for public use, which limits their utilization in data-intensive space weather analytics applications. We introduce a large-scale publicly available PIL data set covering practically the entire solar cycle 24 for applying to various space weather forecasting and analytics tasks. The data set is created using both radial magnetic field (B_r) and line-of-sight (B_LoS) magnetograms from the Solar Dynamics Observatory's Helioseismic and Magnetic Imager Active Region Patches (HARP) that involve 4090 HARP series ranging from 2010 May to 2019 March. This data set includes three PIL-related binary masks of rasters: the actual PILs as per the spatial analysis of the magnetograms, the region of polarity inversion, and the convex hull of PILs, along with time-series-structured metadata extracted from these masks. We also provide a preliminary exploratory analysis of selected features aiming to correlate time series of feature metadata and eruptive activity originating from active regions. We envision that this comprehensive PIL data set will complement existing data sets used for space weather forecasting and benefit research in related areas, specifically in better understanding the PIL structure, evolution, and role in eruptions.

Keywords: Astronomy software
The Pan-STARRS1 z &gt; 5.6 Quasar Survey. II. Discovery of 55 Quasars at 5.6 &lt; z &lt; 6.5. The identification of bright quasars at z ≳ 6 enables detailed studies of supermassive black holes, massive galaxies, structure formation, and the state of the intergalactic medium within the first billion years after the Big Bang. We present the spectroscopic confirmation of 55 quasars at redshifts 5.6 &lt; z &lt; 6.5 and UV magnitudes -24.5 &lt; M 1450 &lt; -28.5 identified in the optical Pan-STARRS1 and near-IR VIKING surveys (48 and 7, respectively). Five of these quasars have independently been discovered in other studies. The quasar sample shows an extensive range of physical properties, including 17 objects with weak emission lines, 10 broad absorption line quasars, and 5 objects with strong radio emission (radio-loud quasars). There are also a few notable sources in the sample, including a blazar candidate at z = 6.23, a likely gravitationally lensed quasar at z = 6.41, and a z = 5.84 quasar in the outskirts of the nearby (D ~ 3 Mpc) spiral galaxy M81. The blazar candidate remains undetected in NOEMA observations of the [C II] and underlying emission, implying a star formation rate &lt;30-70 M ☉ yr-1. A significant fraction of the quasars presented here lies at the foundation of the first measurement of the z ~ 6 quasar luminosity function from Pan-STARRS1 (introduced in a companion paper). These quasars will enable further studies of the high-redshift quasar population with current and future facilities.

Keywords: Active galactic nuclei, Quasars
Spurious Correlations between Galaxies and Multiepoch Image Stacks in the DESI Legacy Surveys. A nonnegligible source of systematic bias in cosmological analyses of galaxy surveys is the on-sky modulation that is caused by foregrounds and variable image characteristics, such as observing conditions. Standard mitigation techniques perform a regression between the observed galaxy density field and sky maps of the potential contaminants. Such maps are ad hoc lossy summaries of the heterogeneous sets of coadded exposures that contribute to the survey. We present a methodology for addressing this limitation, and we extract spurious correlations between the observed distributions of galaxies and arbitrary stacks of single-epoch exposures. We study four types of galaxies (luminous red galaxies, emission-line galaxies, quasars, and Lyman-break galaxies) in the three regions of the DESI Legacy Surveys (North, South, and Dark Energy Survey), resulting in 12 samples with varying levels and types of contamination. We find that the new technique outperforms the traditional ones in all cases, and is able to remove higher levels of contamination. This paves the way for new methods that extract more information from multiepoch galaxy survey data and mitigate large-scale biases more effectively.

Keywords: Observational cosmology, Large-scale structure of the universe
The Fermi-LAT Lightcurve Repository. The Fermi Large Area Telescope (LAT) lightcurve repository (LCR) is a publicly available, continually updated library of gamma-ray lightcurves of variable Fermi-LAT sources generated over multiple timescales. The Fermi-LAT LCR aims to provide publication-quality lightcurves binned on timescales of 3, 7, and 30 days for 1525 sources deemed variable in the source catalog of the first 10 yr of Fermi-LAT observations. The repository consists of lightcurves generated through full likelihood analyses that model the sources and the surrounding region, providing fluxes and photon indices for each time bin. The LCR is intended as a resource for the time-domain and multimessenger communities by allowing users to search LAT data quickly to identify correlated variability and flaring emission episodes from gamma-ray sources. We describe the sample selection and analysis employed by the LCR and provide an overview of the associated data access portal. *For any questions about this work, contact in order: M. Negro, D. Kocevski, J. Valverde, A. Brill, S. Garrappa.

Keywords: Gamma-ray astronomy, Light curves, Active galactic nuclei
Powerful Radio Sources in the Southern Sky. I. Optical Identifications. Since the early sixties, our view of radio galaxies and quasars has been drastically shaped by discoveries made thanks to observations of radio sources listed in the Third Cambridge Catalog and its revised version (3CR). However, the largest fraction of data collected to date on 3CR sources was performed with relatively old instruments, rarely repeated and/or updated. Importantly, the 3CR contains only objects located in the Northern Hemisphere, thus having limited access to new and innovative astronomical facilities. To mitigate these limitations, we present a new catalog of powerful radio sources visible from the Southern Hemisphere, extracted from the GLEAM 4 Jy (G4Jy) catalog and based on equivalent selection criteria as the 3CR. This new catalog, named G4Jy-3CRE, where the E stands for "equivalent," lists a total of 264 sources at decl. below -5° and with 9 Jy limiting sensitivity at ~178 MHz. We explored archival radio maps obtained with different surveys and compared them with optical images available in the Pan-STARRS, DES, and DSS databases to search for optical counterparts of their radio cores. We compared mid-infrared counterparts, originally associated in the G4Jy, with the optical ones identified here, and we present results of a vast literature search carried out to collect redshift estimates for all G4Jy-3CRE sources resulting in a total of 145 reliable z measurements.

Keywords: Extragalactic radio sources
Observational Properties of 155 O- and B-type Massive Pulsating Stars. O- and B-type (OB-type) pulsating stars are important objects for studying the structure and evolution of massive stars through asteroseismology. A large amount of data from various sky surveys provides an unprecedented opportunity to search for and study this kind of variable star. We identify 155 OB-type pulsating stars or candidates, including 38 Oe/Be stars or candidates, from the data observed by TESS, LAMOST, and Gaia, which are almost new. Among the 155 objects, 87 samples are identified as slowly pulsating B (SPB) stars including 37 objects with pure low-frequency and 50 objects with both low- and high-frequency pulsation, and 14 samples are identified as β Cephei pulsating variable (BCEP) stars with both low- and high-frequency pulsation. An H-R diagram shows that these SPB and BCEP stars are mainly located in their instability regions and in the evolutionary stage of the main sequence with mass ranges of 2.5-20 M ⊙ and 7-20 M ⊙, respectively. Two special objects show Fourier spectra similar to BCEP stars but with different positions in H-R, period-temperature (P-T), and period-luminosity (P-L) diagrams. Meanwhile, 52 other targets are identified as candidates of OB-type pulsating stars. We also derive the preliminary results of the P-L relation for SPB and BCEP stars, respectively. This work also indicates that in addition to the H-R diagram, the P-T and P-L diagrams are also very useful for the classification of SPB and BCEP stars. Further detailed analysis of these objects can dramatically increase our understanding of the theories of evolution and structure for massive OB-type pulsating stars.

Keywords: Massive stars, Pulsating variable stars
Application of Deep Reinforcement Learning to Major Solar Flare Forecasting. In this study, we present the application of deep reinforcement learning to the forecasting of major solar flares. For this, we consider full-disk magnetograms at 00:00 UT from the Solar and Heliospheric Observatory/Michelson Doppler Imager (1996-2010) and the Solar Dynamics Observatory/Helioseismic and Magnetic Imager (2011-2019), as well as Geostationary Operational Environmental Satellite X-ray flare data. We apply Deep Q-Network (DQN) and Double DQN, which are popular deep reinforcement learning methods, to predict "Yes or No" for daily M- and X-class flare occurrence. The reward functions, consisting of four rewards for true positive, false positive, false negative, and true negative, are used for our models. The major results of this study are as follows. First, our deep-learning models successfully predict major solar flares with good skill scores, such as HSS, F1, TSS, and ApSS. Second, the performance of our models depends on the reward function, learning method, and target agent update time. Third, the performance of our deep-learning models is noticeably better than that of a convolutional neural network (CNN) model with the same structure: 0.38 (CNN) to 0.44 (ours) for HSS, 0.47 to 0.52 for F1, 0.53 to 0.59 for TSS, and 0.09 to 0.12 for ApSS.

Keywords: The Sun, Solar flares, Neural networks
RETRACTED: Forecasting Solar Cycle 25 Using an Optimized Long Short-term Memory Mode Based on F10.7 and Sunspot Area Data. In this paper, an optimized long short-term memory model is proposed to deal with the smoothed monthly F 10.7 and nonsmoothed monthly sunspot area (SSA) data, aiming to forecast the peak amplitude of both solar activities and the occurring time for Solar Cycle 25 (SC-25), as well as to obtain the maximum amplitude of sunspot number (SSN) and the reaching time according to the relationships between them. The "reforecast" process in the model uses the latest forecast results obtained from the previous forecast as the input for the next forecasting calculation. The forecasting errors between the forecast and observed peak amplitude of F 10.7 for SC-23 and SC-24 are 2.87% and 1.09%, respectively. The results of this evaluation indicator of SSA for SC-21 to SC-24 were 8.85%, 4.49%, 2.88%, and 4.57%, respectively, and the errors for the occurring time were all within 6 months. The forecast peak amplitude of F 10.7 and SSA for SC-25 is 156.3 and 2562.5 respectively, and the maximum values of SSN are calculated as 147.9 and 213 based on F 10.7 and SSA respectively, which implies that SC-25 will be stronger than SC-24, and that SC-25 will reach its peak at the beginning of 2025.

Keywords: Solar cycle, Sunspot number
Image Super-resolution Methods for FY-3E X-EUVI 195 Å Solar Images. Solar eruptions and the solar wind are sources of space weather disturbances, and extreme-ultraviolet (EUV) observations are widely used to research solar activity and space weather forecasts. Fengyun-3E is equipped with the Solar X-ray and Extreme Ultraviolet Imager, which can observe EUV imaging data. Limited by the lower resolution, however, we research super-resolution techniques to improve the data quality. Traditional image interpolation methods have limited expressive ability, while deep-learning methods can learn to reconstruct high-quality images through training on paired data sets. There is a wide variety of super-resolution models. We try these three representative models: Real-ESRGAN combined with generative adversarial networks, residual channel-attention networks (RCAN) based on channel attention, and SwinIR, based on self-attention. Instruments on different satellites differ in observation time, angle, and resolution, so we selected Solar Dynamics Observatory/Atmospheric Imaging Assembly (SDO/AIA) 193 Å images with similar wavelengths as a reference and used a feature-based method for image registration to eliminate slight deformations to build training data sets. Finally, we compare the above methods in their evaluation metrics and visual quality. RCAN has the highest peak signal-to-noise ratio and structural similarity evaluation. Real-ESRGAN model is the best in the Learned Perceptual Image Patch Similarity index, and its results visually show that it has more highly detailed textures. The corrected super-resolution results can complement the SDO/AIA data to provide solar EUV images with a higher temporal resolution for space weather forecasting and solar physics research.

Keywords: Solar ultraviolet emission
Hard X-Ray to Radio Multiwavelength SED Analysis of Local U/LIRGs in the GOALS Sample with a Self-consistent AGN Model including a Polar-dust Component. We conduct hard X-ray to radio multiwavelength spectral energy distribution (SED) decomposition for 57 local luminous and ultraluminous infrared galaxies observed with the Nuclear Spectroscopic Telescope Array and/or Swift/Burst Alert Telescope in the GOALS sample. We modify the latest SED-fitting code X-CIGALE by implementing the infrared (IR) CLUMPY model, allowing us to conduct the multiwavelength study with the X-ray torus model XCLUMPY self-consistently. Adopting the torus parameters obtained by the X-ray fitting, we estimate the properties of the host galaxies, active galactic nucleus (AGN) tori, and polar dust. The star formation rates (SFRs) become larger with merger stage and most of them are above the main sequence. The SFRs are correlated with radio luminosity, indicating starburst emission is dominant in the radio band. Although polar-dust extinction is much smaller than torus extinction, the UV-to-IR (mainly IR) polar dust luminosities are ~2 times larger than the torus ones. The polar-dust temperature decreases while the physical size, estimated by the temperature and dust sublimation radius, increases with AGN luminosity from a few tens of parsec (early mergers) to kiloparsec scales (late mergers), where the polar dust likely comes from expanding (i.e., evolving) dusty outflows. A comparison between the SFRs and intrinsic AGN luminosities suggests that starbursts occur first and AGNs arise later, and overall their growth rates follow the simultaneous coevolution local galaxy-SMBH mass relation. We confirm the coexistence of intense starbursts, AGNs, and large-scale outflows in late mergers, supporting a standard AGN feedback scenario.

Keywords: Optical observation, X-ray active galactic nuclei, Active galactic nuclei, Infrared galaxies, Radio continuum emission, Infrared photometry
Firefly: A Browser-based Interactive 3D Data Visualization Tool for Millions of Data Points. We present Firefly, a new browser-based interactive tool for visualizing 3D particle data sets. On a typical personal computer, Firefly can simultaneously render and enable real-time interactions with ≳10 million particles, and can interactively explore data sets with billions of particles using the included custom-built octree render engine. Once created, viewing a Firefly visualization requires no installation and is immediately usable in most modern internet browsers simply by visiting a URL. As a result, a Firefly visualization works out-of-the-box on most devices including smartphones and tablets. Firefly is primarily developed for researchers to explore their own data, but can also be useful to communicate results to researchers and/or collaborators and as an effective public outreach tool. Every element of the user interface can be customized and disabled, enabling easy adaptation of the same visualization for different audiences with little additional effort. Creating a new Firefly visualization is simple with the provided Python data preprocessor that translates input data to a Firefly-compatible format and provides helpful methods for hosting instances of Firefly both locally and on the internet. In addition to visualizing the positions of particles, users can visualize vector fields (e.g., velocities) and also filter and color points by scalar fields. We share three examples of Firefly applied to astronomical data sets: (1) the FIRE cosmological zoom-in simulations, (2) the SDSS galaxy catalog, and (3) Gaia Data Release 3. A gallery of additional interactive demos is available at alexbgurvi.ch/Firefly.

Keywords: Open source software, Astronomy data visualization
Rubin LSST Observing Strategies to Maximize Volume and Uniformity Coverage of Star-forming Regions in the Galactic Plane. A complete map of the youngest stellar populations of the Milky Way in the era of all-sky surveys is one of the most challenging goals in modern astrophysics. The characterization of the youngest stellar components is crucial not only for a global overview of the Milky Way's structure, of the Galactic thin disk, and its spiral arms, but also for local studies. In fact, the identification of star-forming regions (SFRs) and the comparison with the environment in which they form are also fundamental to put SFRs in the context of the surrounding giant molecular clouds and to understand still unknown physical mechanisms related to star and planet formation processes. In 10 yr of observations, the Vera C. Rubin Legacy Survey of Space and Time (Rubin LSST) will achieve an exquisite photometric depth that will allow us to significantly extend the volume within which we will be able to discover new SFRs and to enlarge the region of our own Galaxy we have detailed knowledge about. We describe here a metric that estimates the total number of young stars with ages t &lt; 10 Myr and masses &gt;0.3 M ⊙ that will be detected with the Rubin LSST observations in the gri bands at a 5σ magnitude significance. We examine the results of our metric adopting the most recent simulated Rubin LSST survey strategies in order to evaluate the impact that different observing strategies might have on our science case.

Keywords: Young stellar objects, Milky Way Galaxy, Interstellar medium, Star clusters
The MUSE Ultra Deep Field (MUDF). III. Hubble Space Telescope WFC3 Grism Spectroscopy and Imaging. We present extremely deep Hubble Space Telescope (HST) Wide Field Camera 3 (WFC3) observations of the MUSE Ultra Deep Field. This unique region of the sky contains two quasars at z ≈ 3.22 that are separated by only ~500 kpc, providing a stereoscopic view of gas and galaxies in emission and absorption across ~10 billion years of cosmic time. We have obtained 90 orbits of HST WFC3 G141 near-infrared grism spectroscopy of this field in a single pointing, as well as 142 hr of optical spectroscopy with the Very Large Telescope Multi Unit Spectroscopic Explorer (MUSE). The WFC3 (F140W, F125W, and F336W) and archival WFPC2 (F702W and F450W) imaging provides five-filter photometry that we use to detect 3375 sources between z ≈ 0-6, including 1536 objects in a deep central pointing with both spectroscopic and photometric coverage. The F140W and F336W mosaics reach exceptional depths of m AB ≈ 28 and 29, respectively, providing near-infrared and rest-frame ultraviolet information for 1580 sources, and we reach 5σ continuum detections for objects as faint as m AB ≈ 27 in the grism spectra. The extensive wavelength coverage of MUSE and WFC3 allows us to measure spectroscopic redshifts for 419 sources, down to galaxy stellar masses of log(M/M ☉) ≈7 at z ≈ 1-2. In this publication, we provide the calibrated HST data and source catalogs as High Level Science Products for use by the community, which includes photometry, morphology, and redshift measurements that enable a variety of studies aimed at advancing our models of galaxy formation and evolution in different environments.

Keywords: Observational cosmology, Astronomical techniques, Galaxy photometry, Galaxy abundances, Galaxy evolution, High-redshift galaxies
Light-curve Recovery with the Vera Rubin Observatory's LSST. I. Pulsating Stars in Local Group Dwarf Galaxies. This investigation is mainly focused on the LSST Survey Strategy Optimization process, a bottom-up approach that turned out to be quite effective in involving the scientific community in the definition of the LSST observing strategy. We are mainly interested in using radial variables (RR Lyrae, classical Cepheids, long-period variables) as stellar tracers and distance indicators, and we developed a new tool called PulsationStarRecovery to quantify the recovery of the light-curve period and amplitude from an LSST-simulated time series. The outputs of this code are pulsation parameters (period, amplitude, mean magnitude) together with quantitative information concerning the difference between the shape of the light curve and template light curves. Furthermore, we apply the newborn metric to simulate LSST observations and recovery of different types of pulsating stars hosted by selected massive stellar systems (19 Local Group dwarf galaxies and the Large Magellanic Cloud) to show how the recovery changes according to distance and variable-star type. We show that this exercise is essential to understand the potential of LSST in this field since excellent recovery is necessary to optimize the use of predicted period-luminosity, period-amplitude, and color-color relations to constrain the cosmic distance scale and the metallicity distribution function of different stellar populations.

Keywords: Surveys, Dwarf galaxies, Light curve classification , Pulsating variable stars
Atomic Transition Probabilities for Transitions of Si I and Si II and the Silicon Abundances of Several Very Metal-poor Stars. We report new measurements of branching fractions for 20 UV and blue lines in the spectrum of neutral silicon (Si I) originating in the 3s 23p4s 3Po 1,2,1Po 1, and 3s3p 3 1Do 1,2 upper levels. Transitions studied include both strong, nearly pure LS multiplets as well as very weak spin-forbidden transitions connected to these upper levels. We also report a new branching fraction measurement of the 4P1/2-2Po 1/2,3/2 intercombination lines in the spectrum of singly ionized silicon (Si II). The weak spin-forbidden lines of Si I and Si II provide a stringent test on recent theoretical calculations, to which we make comparison. The branching fractions from this study are combined with previously reported radiative lifetimes to yield transition probabilities and log(gf) values for these lines. We apply these new measurements to abundance determinations in five metal-poor stars. ∗ Based on observations made with the NASA/ESA Hubble Space Telescope (HST), obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc. under NASA contract NAS 5-26555. Other data have been obtained from the European Southern Observatory (ESO) Science Archive Facility; and the Keck Observatory Archive, which is operated by the W. M. Keck Observatory and the NASA Exoplanet Science Institute, under contract with NASA. These data are associated with HST programs GO-7402, GO-14161, and GO-14232; ESO programs 66.D-0636(A), 073.D-0024(A), and 095.D-0504(A); and Keck program H41aH.

Keywords: Atomic spectroscopy, Transition probabilities, Stellar abundances