Sazuna/UAT_keywords huggingface dataset:
The Sloan Digital Sky Survey Reverberation Mapping Project: the XMM-Newton X-Ray Source Catalog and Multiband Counterparts. The XMM-RM project was designed to provide X-ray coverage of the Sloan Digital Sky Survey Reverberation Mapping (SDSS-RM) field. Forty-one XMM-Newton exposures, placed surrounding the Chandra AEGIS field, were taken, covering an area of 6.13 deg2 and reaching a nominal exposure depth of ∼15 ks. We present an X-ray catalog of 3553 sources detected in these data, using a PSF-fitting algorithm and a sample selection threshold that produces a ∼5% fraction of spurious sources. In addition to the PSF-fitting likelihood, we calculate a second source reliability measure based on Poisson theory using source and background counts within an aperture. Using the Poissonian likelihood, we select a subsample with a high purity and find that it has number count profiles similar to previous X-ray surveys. The Bayesian method "NWAY" was employed to identify counterparts of the X-ray sources from the optical Legacy and the IR unWISE catalogs, using a two-dimensional unWISE magnitude-color prior created from optical/IR counterparts of Chandra X-ray sources. A significant number of the optical/IR counterparts correspond to sources with low detection likelihoods, proving the value of retaining the low-likelihood detections in the catalog. A total of 932 of the XMM-RM sources are covered by SDSS spectroscopic observations, where 89% of them are classified as active galactic nuclei, and 71% of these active galactic nuclei are in the SDSS-RM quasar catalog. Among the SDSS-RM quasars, 80% are detectable at the depth of the XMM observations.

Keywords: Supermassive black holes, Quasars, X-ray point sources, Astronomy data analysis, X-ray active galactic nuclei, Active galactic nuclei
Yonsei Evolutionary Population Synthesis (YEPS) Model. III. Surface Brightness Fluctuation of Normal and Helium-enhanced Simple Stellar Populations. We present an evolutionary population synthesis model of the surface brightness fluctuation (SBF) for normal and He-enriched simple stellar populations (SSPs). While our SBF model for the normal He population agrees with other existing models, the He-rich population, containing hotter horizontal branch stars and brighter red clump stars than the normal He population, entails a substantial change in the SBF of SSPs. We show that the SBF magnitudes are affected by He-rich populations at least ∼0.3 mag even in I- and near-infrared bands at given colors, from which the SBF-based distances are often derived. Due to uncertainties both in observations and models, however, the SBFs of Galactic globular clusters and early-type galaxies do not allow verifying the He-enriched model. We propose that when combined with independent metallicity and age indicators such as Mg2 and Hβ, the UV and optical SBFs can readily detect underlying He-rich populations in unresolved stellar systems at a distance out to ≳20 Mpc. A full set of the spectro-photometric and SBF data for SSPs from the Yonsei Evolutionary Population Synthesis (YEPS) model is available for download at http://cosmic.yonsei.ac.kr/YEPS.htm.

Keywords: Globular star clusters, Horizontal branch stars, Galaxy distances, Stellar abundances, Galaxy stellar content, Stellar distance, Stellar evolution
Physics of Eclipsing Binaries. V. General Framework for Solving the Inverse Problem. PHOEBE 2 is a Python package for modeling the observables of eclipsing star systems, but until now it has focused entirely on the forward model—that is, generating a synthetic model given fixed values of a large number of parameters describing the system and the observations. The inverse problem, obtaining orbital and stellar parameters given observational data, is more complicated and computationally expensive as it requires generating a large set of forward models to determine which set of parameters and uncertainties best represents the available observational data. The process of determining the best solution and also of obtaining reliable and robust uncertainties on those parameters often requires the use of multiple algorithms, including both optimizers and samplers. Furthermore, the forward model of PHOEBE has been designed to be as physically robust as possible, but it is computationally expensive compared to other codes. It is useful, therefore, to use whichever code is most efficient given the reasonable assumptions for a specific system, but learning the intricacies of multiple codes presents a barrier to doing this in practice. Here we present release 2.3 of PHOEBE (publicly available from http://phoebe-project.org), which introduces a general framework for defining and handling distributions on parameters and utilizing multiple different estimation, optimization, and sampling algorithms. The presented framework supports multiple forward models, including the robust model built into PHOEBE itself.

Keywords: Eclipsing binary stars
Sub-ion Scale Compressive Turbulence in the Solar Wind: MMS Spacecraft Potential Observations. Compressive plasma turbulence is investigated at sub-ion scales in the solar wind using both the Fast Plasma Investigation (FPI) instrument on the Magnetospheric MultiScale mission (MMS), as well as using calibrated spacecraft potential data from the Spin Plane Double Probe (SDP) instrument. The data from FPI allow the sub-ion scale region (fsc ≳ 1 Hz) to be investigated before the instrumental noise becomes significant at a spacecraft frame frequency of fsc ≈ 3 Hz. Whereas the calibrated spacecraft potential allows a measurement up to fsc ≈ 40 Hz. In this work, we give a detailed description of density estimation in the solar wind using the spacecraft potential measurement from the SDP instrument on MMS. Several intervals of solar wind plasma have been processed using the methodology described and are made available. One of the intervals is investigated in more detail and the power spectral density of the compressive fluctuations is measured from the inertial range to the sub-ion range. The morphology of the density spectra can be explained by either a cascade of Alfvén waves and slow waves at large scales and kinetic Alfvén waves at sub-ion scales or more generally by the Hall effect. Using electric field measurements, the two hypotheses are discussed.

Keywords: Interplanetary turbulence, Space plasmas, Solar wind, Plasma physics
Matched Photometric Catalogs of GALEX UV Sources with Gaia DR2 and SDSS DR14 Databases (GUVmatch). We have matched the ultraviolet (UV) sources in GUVcat_AIS with optical databases that have similar depth and wide sky coverage. GUVcat_AIS has Galaxy Evolution Explorer (GALEX) far-UV (FUV, λeff ∼ 1528 Å) and near-UV (NUV, λeff ∼ 2310 Å) photometry of ≈83 million sources, covering 24,788 square degrees of the sky, with a typical depth of FUV = 19.9 and NUV = 20.8 AB mag. Matches with Gaia and the Sloan Digital Sky Survey (SDSS) databases are presented here. Gaia data release 2 (DR2), covering the entire GUVcat footprint, detected about one-third of the GUVcat_AIS sources. We found 31,925,294 Gaia DR2 counterparts to 30,024,791 GUVcat_AIS unique sources, with photometry in the Gaia G band and often also in Gaia BP and RP bands; 26,275,572 matches have a parallax measurement, 21,084,628, 18,588,140, and 16,357,505 have a parallax error less than 50%, 30%, and 20%, respectively. The match with SDSS data release 14 (DR14) yields 23,310,532 counterparts to 22,207,563 unique GUVcat_AIS sources, 10,167,460 of which are pointlike, over a total overlap area of ≈11,100 square degrees (Bianchi et al. 2019). SDSS adds five optical magnitudes to the UV photometry : u, g, r, i, z, and optical spectra of 860,224 matched sources. We used a match radius of 3″, consistent with previous works, although the positions agree to ≲1"5 for the majority of (pointlike) matched sources, in order to identify possible multiple matches whose UV flux could be unresolved in GALEX imaging. The catalogs can be trimmed to a tighter match radius using the provided separation. The multiband photometry is used to identify classes of astrophysical objects that are prominent in UV, to characterize the content of the GUVmatch catalogs, where stars in different evolutionary stages, quasi-stellar objects, and galaxies can be separated.

Keywords: Galaxies, Sky surveys, Astronomy databases, Quasars, Surveys, White dwarf stars, Galactic bulge, OB stars, Main sequence stars, Star counts, Milky Way Galaxy, Catalogs
ZBLLAC: A Spectroscopic Database of BL Lacertae Objects. This paper describes the database of optical spectra of BL Lacertae (BLL) objects (Z BLL objects) available at https://web.oapd.inaf.it/zbllac/. At present, it contains calibrated spectra for 295 BLL. For about 35% of them, we report a firm measure of redshift z, while for 35 sources we set a lower limit on z based on the detection of intervening absorption systems, mainly ascribed to Mg II (λ2800 Å). We report here on the architecture of the database and on its website front-end that permits us to filter, query, and interactively explore the data. We discuss some properties of the objects in the present data set by giving the distribution of the redshifts and reporting on the detected emission lines, which turn out to be mainly forbidden and ascribed to [O II] (λ3737 Å) and [O III] (λ5007 Å). Finally, we discuss on intervening absorption systems detected in 35 BLLs that allow us to set lower limits to their distance.

Keywords: Blazars, Jets, High energy astrophysics
A Broadband Digital Spectrometer for the Deep Space Network. The Deep Space Network (DSN) enables NASA to communicate with its spacecraft in deep space. By virtue of its large antennas, the DSN can also be used as a powerful instrument for radio astronomy. Specifically, the Deep Space Station (DSS)-43, the 70 m antenna at the Canberra Deep Space Communications Complex (CDSCC), has a K-band radio astronomy system covering a 10 GHz bandwidth at 17-27 GHz. This spectral range covers a number of atomic and molecular lines, produced in a rich variety of interstellar gas conditions. Lines include hydrogen radio recombination lines (RRLs), cyclopropenylidene (C3H2), water masers (H2O), and ammonia (NH3). A new high-resolution spectrometer was deployed at CDSCC in 2019 November and connected to the K-band down converter. The spectrometer has a total bandwidth of 16 GHz. Such a large total bandwidth enables, for example, the simultaneous observations of a large number of RRLs, which can be combined together to significantly improve the sensitivity of these observations. The system has two firmware modes: (1) a 65k-pt fast Fourier transform to provide 32,768 spectral channels at 30.5 kHz and (2) a 16k-pt polyphase filter bank to provide 8192 spectral channels with a 122 kHz resolution. The observation process is designed to maximize autonomy, from the principle investigator&amp;'s inputs to the output data in FITS file format. We present preliminary mapping observations of hydrogen RRLs in Orion KL mapping taken using the new spectrometer.

Keywords: Spectrometers, Astronomical instrumentation
The Chandra Deep Wide-field Survey: A New Chandra Legacy Survey in the Boötes Field. I. X-Ray Point Source Catalog, Number Counts, and Multiwavelength Counterparts. We present a new, ambitious survey performed with the Chandra X-ray Observatory of the 9.3 deg2 Boötes field of the NOAO Deep Wide-Field Survey. The wide field probes a statistically representative volume of the universe at high redshift. The Chandra Deep Wide-field Survey exploits the excellent sensitivity and angular resolution of Chandra over a wide area, combining 281 observations spanning 15 yr, for a total exposure time of 3.4 Ms, and detects 6891 X-ray point sources down to limiting fluxes of 4.7 × 10-16, 1.5 × 10-16, and 9 ×10-16 erg cm-2 s-1 in the 0.5-7, 0.5-2, and 2-7 keV bands, respectively. The robustness and reliability of the detection strategy are validated through extensive, state-of-the-art simulations of the whole field. Accurate number counts, in good agreement with previous X-ray surveys, are derived thanks to the uniquely large number of point sources detected, which resolve 65.0% ± 12.8% of the cosmic X-ray background between 0.5 and 2 keV and 81.0% ± 11.5% between 2 and 7 keV. Exploiting the wealth of multiwavelength data available on the field, we assign redshifts to ∼94% of the X-ray sources, estimate their obscuration, and derive absorption-corrected luminosities. We provide an electronic catalog containing all of the relevant quantities needed for future investigations.

Keywords: X-ray astronomy, AGN host galaxies, Active galactic nuclei, X-ray active galactic nuclei, Catalogs
The Pan-STARRS Data-processing System. The Pan-STARRS data-processing system is responsible for the steps needed to downloaded, archive, and process all images obtained by the Pan-STARRS telescopes, including real-time detection of transient sources such as supernovae and moving objects including potentially hazardous asteroids. With a nightly data volume of up to 4 TB and an archive of over 4 PB of raw imagery, Pan-STARRS is solidly in the realm of Big Data astronomy. The full data-processing system consists of several subsystems covering the wide range of necessary capabilities. This article describes the Image Processing Pipeline and its connections to both the summit data systems and the outward-facing systems downstream. The latter include the Moving Object Processing System (MOPS) and the public database: the Published Science Products Subsystem.

Keywords: Sky surveys, Astronomy databases, Astronomy data analysis, Astronomical techniques, Astrometry, Photometry, Astronomy data reduction
Pan-STARRS Pixel Processing: Detrending, Warping, Stacking. The Pan-STARRS1 (PS1) Science Consortium has carried out a set of imaging surveys using the 1.4 gigapixel GPC1 camera on the PS1 telescope. As this camera is composed of many individual electronic readouts and covers a very large field of view, great care was taken to ensure that the many instrumental effects were corrected to produce the most uniform detector response possible. We present the image-detrending steps used as part of the processing of the data contained within the public release of Pan-STARRS1 Data Release 1 (DR1). In addition to the single image processing, the methods used to transform the 375,573 individual exposures into a common sky-oriented grid are discussed, as well as those used to produce both the image stack and difference combination products.

Keywords: CCD observation, Sky surveys, Astronomy data reduction
Pan-STARRS Pixel Analysis: Source Detection and Characterization. Over 3 billion astronomical sources have been detected in the more than 22 million orthogonal transfer CCD images obtained as part of the Pan-STARRS1 3π survey. Over 85 billion instances of those sources have been automatically detected and characterized by the Pan-STARRS Image Processing Pipeline photometry software, psphot. This fast, automatic, and reliable software was developed for the Pan-STARRS project but is easily adaptable to images from other telescopes. We describe the analysis of the astronomical sources by psphot in general as well as for the specific case of the third processing version used for the first two public releases of the Pan-STARRS 3π Survey data.

Keywords: CCD photometry, Astronomical object identification, Astronomy data analysis, Astronomical techniques, Galaxy photometry, Astrometry, Astronomy data reduction
Pan-STARRS Photometric and Astrometric Calibration. We present the details of the photometric and astrometric calibration of the Pan-STARRS1 3π Survey. The photometric goals were to reduce the systematic effects introduced by the camera and detectors, and to place all of the observations onto a photometric system with consistent zero-points over the entire area surveyed, the ≈30,000 deg2 north of δ = -30°. Using external comparisons, we demonstrate that the resulting photometric system is consistent across the sky to between 7 and 12.4 mmag depending on the filter. For bright stars, the systematic error floor for individual measurements is (σg, σr, σi, σz, σy) = (14, 14, 15, 15, 18) mmag. The astrometric calibration compensates for similar systematic effects so that positions, proper motions, and parallaxes are reliable as well. The bright-star systematic error floor for individual astrometric measurements is 16 mas. The Pan-STARRS Data Release 2 (DR2) astrometric system is tied to the Gaia DR1 coordinate frame with a systematic uncertainty of ∼5 mas.

Keywords: CCD photometry, Sky surveys, Astronomy databases, Surveys, Flux calibration, Astrometry, Photometry, Proper motions
The Pan-STARRS1 Database and Data Products. This paper describes the organization of the database and the catalog data products from the Pan-STARRS1 3π Steradian Survey. The catalog data products are available in the form of an SQL-based relational database from MAST, the Mikulski Archive for Space Telescopes at STScI. The database is described in detail, including the construction of the database, the provenance of the data, the schema, and how the database tables are related. Examples of queries for a range of science goals are included.

Keywords: Astrometry, Sky surveys, Astronomy databases, Photometry
Energy-preserving Integrators for Post-Newtonian Lagrangian Dynamics. Equations of motion derived from the Euler-Lagrange formula are usually implicit differential equations in terms of accelerations for the post-Newtonian (PN) Lagrangian dynamics of general relativistic problems. Meanwhile, the Legendre transform is in a nonclosed form due to the high nonlinearity of the velocity in the PN Lagrangian. To numerically integrate the exact implicit equations of motion rather than the truncated equations, the nontruncated strategy with an additional iteration for the Legendre transform is needed. In this paper, we aim at exploring energy-preserving methods accompanying the nontruncated strategy for the PN Lagrangian dynamics, once noticing that energy preservation as well as symplecticity is one of the most important properties of the Hamiltonian system that is completely equivalent to the PN Lagrangian. Incorporating the nontruncated strategy into the continuous-stage Runge-Kutta method, we thus propose a novel class of practical energy-preserving schemes. Numerical results from the PN Lagrangian circular restricted three-body problem and the spinning compact binaries show that the proposed numerical scheme is of high efficiency and can preserve energy nearly as accurately as machine precision.

Keywords: Computational methods, Computational astronomy, Compact objects
FIRST Winged Radio Galaxies with X and Z Symmetry. X-shaped radio galaxies (XRGs) are a subclass of radio sources that exhibit a pair of secondary low surface brightness radio lobes oriented at an angle to the primary high surface brightness lobes. Sometimes, the secondary low brightened lobes emerge from the edges of the primary high brightened lobes and form a Z-symmetric morphology. We present a systematical search result for XRGs and Z-shaped radio galaxies (ZRGs) from the VLA Faint Images of the Radio Sky at Twenty-Centimeters (VLA FIRST) Survey at 1.4 GHz. Our search yields a total of 296 number of radio sources, out of which 161 are XRGs and 135 are ZRGs. We have also made optical identification of these sources from the different available literature. J1124 + 4325 and J1319 + 0502 are the farthest known XRG and ZRG, respectively. We have estimated spectral index and radio luminosity of these radio sources and made a comparative study with previously detected XRGs and ZRGs. The average value of luminosities for XRGs is higher than that of ZRGs. With the help of a large sample size of the newly discovered XRGs and ZRGs, various statistical properties of these sources are studied. Out of 161 XRGs presented in the current paper, 70% (113) are FR II radio galaxies and 13% (20) are FR I radio galaxies. For 28 XRGs, the morphology is complex and could not be classified. For XRGs, the statistical studies are done on the angle between the major axis and minor axis and the relative size of the major and minor axes. For the ZRGs a statistical study is done on the angular size.

Keywords: Quasars, Surveys, Radio continuum emission, Active galactic nuclei, Interferometric correlation, Catalogs
A Coupled Guiding Center-Boris Particle Pusher for Magnetized Plasmas in Compact-object Magnetospheres. We present a novel numerical scheme for simulating the motion of relativistic charged particles in magnetospheres of compact objects, typically filled with highly magnetized collisionless plasmas. The new algorithm is based on a dynamic switch between the full system of equations of motion and a guiding-center approximation. The switch between the two formulations is based on the magnetization of the plasma particles, such that the dynamics are accurately captured by the guiding-center motion even when the gyrofrequency is underresolved by the time step. For particles with a large gyroradius, due to acceleration in, e.g., reconnecting current sheets, the algorithm adaptively switches to solve the full equations of motion instead. The new scheme is directly compatible with standard particle-in-cell codes, and is readily applicable in curved spacetimes via a dedicated covariant formulation. We test the performance of the coupled algorithm by evolving charged particles in electromagnetic configurations of reconnecting current sheets in magnetized plasma, obtained from special- and general-relativistic particle-in-cell simulations. The new coupled pusher is capable of producing highly accurate particle trajectories even when the time step is many orders of magnitude larger than the gyroperiod, substantially reducing the restrictions of the temporal resolution.

Keywords: Neutron stars, Space plasmas, Compact objects, Plasma physics
Swift/UVOT+MaNGA (SwiM) Value-added Catalog. We introduce the Swift/UVOT+MaNGA (SwiM) value-added catalog, which comprises 150 galaxies that have both Sloan Digital Sky Survey (SDSS)/MaNGA integral field spectroscopy and archival Swift/UVOT near-UV (NUV) images. The similar angular resolution between the three Swift/UVOT NUV images and the MaNGA maps allows for a high-resolution comparison of optical and NUV indicators of star formation, crucial for constraining quenching and attenuation in the local universe. The UVOT NUV images, SDSS images, and MaNGA emission line and spectral index maps have all been spatially matched and reprojected to match the point-spread function (PSF) and pixel sampling of the Swift/UVOT uvw2 images and are presented in the same coordinate system for each galaxy. The spectral index maps use the definition first adopted by Burstein et al., which makes it more convenient for users to compute spectral indices when binning the maps. Spatial covariance is properly taken into account in propagating the uncertainties. We also provide a catalog that includes PSF-matched aperture photometry in the SDSS optical and Swift NUV bands. In an earlier companion paper, we used a subset of these galaxies to explore the attenuation laws of kiloparsec-sized star-forming regions. The catalog, maps for each galaxy, and associated data models are publicly available on the SDSS website.

Keywords: Catalogs, Astronomy data analysis, Star formation, Ultraviolet photometry, Spectroscopy, Sloan photometry, Galaxies