Sazuna/UAT_keywords huggingface dataset:
Imaging and Modeling Data from the Hydrogen Epoch of Reionization Array. We analyze data from the Hydrogen Epoch of Reionization Array (HERA). This is the third in a series of papers on the closure phase delay spectrum technique designed to detect the H I 21 cm emission from cosmic reionization. We present the details of the data and models employed in the power spectral analysis and discuss limitations to the process. We compare images and visibility spectra made with HERA data to parallel quantities generated from sky models based on the Galactic and Extra-Galactic All-Sky MWA (GLEAM) survey, incorporating the HERA telescope model. We find reasonable agreement between images made from HERA data with those generated from the models, down to the confusion level. For the visibility spectra, there is broad agreement between model and data across the full band of ∼80 MHz. However, models with only GLEAM sources do not reproduce a roughly sinusoidal spectral structure at the tens of percent level seen in the observed visibility spectra on scales of ∼10 MHz on 29 m baselines. We find that this structure is likely due to diffuse Galactic emission, predominantly the Galactic plane, filling the far sidelobes of the antenna primary beam. We show that our current knowledge of the frequency dependence of the diffuse sky radio emission, and the primary beam at large zenith angles, is inadequate to provide an accurate reproduction of the diffuse structure in the models. We discuss some implications arising due to this missing structure in the models, in terms of calibration, and in the search for the H I 21 cm signal, as well as possible mitigation techniques.

Keywords: Cosmology, Cosmological evolution, Radio interferometry, Reionization
Probing the Galactic Halo with RR Lyrae Stars. I. The Catalog. We present a catalog of 5290 RR Lyrae stars (RRLs) with metallicities estimated from spectra of the LAMOST Experiment for Galactic Understanding and Exploration (LEGUE) and the Sloan Extension for Galactic Understanding and Exploration (SEGUE) surveys. Nearly 70% of them (3642 objects) also have systemic radial velocities measured. Given the pulsating nature of RRLs, metallicity estimates are based on spectra of individual exposures that have been matched with their synthetic templates. The systemic radial velocities are measured by fitting the observed velocity as a function of phase assuming an empirical pulsating velocity template curve. Various tests show that our analyses yield metallicities with a typical precision of 0.20 dex and systemic radial velocities with uncertainties ranging from 5 to 21 km s-1 (depending on the number of radial-velocity measurements available for a given star). Based on the well-calibrated near-infrared PMW1Z or PMK_{s}Z, and MV-[Fe/H] relations, precise distances are derived for these RRLs. Finally, we include Gaia DR2 proper motions in our catalog. The catalog should be very useful for various Galactic studies, especially of the Galactic halo.

Keywords: Galaxy structure, Chemical abundances, RR Lyrae variable stars, Galaxy abundances, Milky Way stellar halo
The CatWISE Preliminary Catalog: Motions from WISE and NEOWISE Data. CatWISE is a program to catalog sources selected from combined WISE and NEOWISE all-sky survey data at 3.4 and 4.6 &amp;mgrm (W1 and W2). The CatWISE Preliminary Catalog consists of 900,849,014 sources measured in data collected from 2010 to 2016. This data set represents four times as many exposures and spans over 10 times as large a time baseline as that used for the AllWISE Catalog. CatWISE adapts AllWISE software to measure the sources in coadded images created from six-month subsets of these data, each representing one coverage of the inertial sky, or epoch. The catalog includes the measured motion of sources in eight epochs over the 6.5 yr span of the data. From comparison to Spitzer, signal-to-noise ratio = 5 limits in magnitudes in the Vega system are W1 &amp;equals 17.67 and W2 = 16.47, compared to W1 &amp;equals 16.96 and W2 = 16.02 for AllWISE. From comparison to Gaia, CatWISE positions have typical accuracies of 50 mas for stars at W1 &amp;equals 10 mag and 275 mas for stars at W1 = 15.5 mag. Proper motions have typical accuracies of 10 mas yr-1 and 30 mas yr-1 for stars with these brightnesses, an order of magnitude better than from AllWISE. The catalog is available in the WISE/NEOWISE Enhanced and Contributed Products area of the NASA/IPAC Infrared Science Archive.

Keywords: Brown dwarfs, Sky surveys, Infrared astronomy, Proper motions, Catalogs
Large-scale Multiconfiguration Dirac-Hartree-Fock Calculations for Astrophysics: n = 4 Levels in P-like Ions from Mn XI to Ni XIV. Using the multiconfiguration Dirac-Hartree-Fock and the relativistic configuration interaction methods, a consistent set of transition energies and radiative transition data for the lowest 546 (623, 701, and 745) states of the 3p43d, 3s3p23d2, 3s3p34p, 3s3p4, 3s23d3, 3s23p23d, 3s23p24d, 3s23p24s, 3p33d2, 3p5, 3s3p3d3, 3s3p33d, 3s3p34s, 3s23p3d2, 3s23p24p, and 3s23p3 configurations in Mn XI (Fe XII, Co XIII, and Ni XIV) is provided. The comparison between calculated excitation energies for the n = 4 states and available experimental values for Fe XII indicate that the calculations are highly accurate, with uncertainties of only a few hundred cm-1. Lines from these states are prominent in the soft X-rays. With the present calculations, several recent new identifications are confirmed. Other identifications involving 3p24d levels in Fe XII that were found to be questionable are discussed and a few new assignments are recommended. As some n = 4 states of the other ions also show large discrepancies between experimental and calculated energies, we reassess their identification. The present study provides highly accurate atomic data for the n = 4 states of P-like ions of astrophysical interest, for which experimental data are scarce.

Keywords: Laboratory astrophysics, Atomic data benchmarking
Deciphering the Large-scale Environment of Radio Galaxies in the Local Universe. II. A Statistical Analysis of Environmental Properties. In our previous analysis we investigated the large-scale environment of two samples of radio galaxies (RGs) in the local universe (I.e., with redshifts zsrc ≤ 0.15), classified as FR I and FR II on the basis of their radio morphology. The analysis was carried out using (I) extremely homogeneous catalogs and (II) a new method, known as cosmological overdensity, to investigate their large-scale environments. We concluded that, independently of the shape of their radio extended structure, RGs inhabit galaxy-rich large-scale environments with similar characteristics and richness. In the present work, we first highlight additional advantages of our procedure, which does not suffer cosmological biases and/or artifacts, and then we carry out an additional statistical test to strengthen our previous results. We also investigate properties of RG environments using those of the cosmological neighbors. We find that large-scale environments of both FR Is and FR IIs are remarkably similar and independent of the properties of central RG. Finally, we highlight the importance of comparing radio sources in the same redshift bins to obtain a complete overview of their large-scale environments.

Keywords: Galaxy clusters, Active galaxies, Relativistic jets, Astrostatistics, Radio galaxies
Comprehensive Data for Depolarization of the Second Solar Spectrum by Isotropic Collisions with Neutral Hydrogen. Interpretation of the second solar spectrum (SSS) requires a complete determination of the depolarizing effect due to collisions with neutral hydrogen. In this paper, we provide comprehensive collision data for simple atoms, complex atoms, and atoms with hyperfine structure. Grids of interaction potentials were computed for a large range of effective quantum numbers n* that characterize states of hypothetical simple atoms. After that, the Schrödinger equation is solved to calculate the collisional transition matrix for each value of n*. Thus, we constructed a database of collisional polarization transfer and depolarization rates of all p-, d-, and f-states of simple atoms. The obtained results are fitted to deduce 48 variation laws, leading to the determination of all depolarization and polarization transfer rates of solar simple atoms. These laws are general and can be applied for any simple atom. We demonstrate how these laws can be used to efficiently obtain the collision rates associated with complex atoms, as well as with atoms with hyperfine structure. We show how the reader may use the variation laws to reproduce all new (de)polarization rates of this paper, as well as all rates of our previous papers published since 2003. Accuracy of our variation laws is discussed. Our analytical laws can be easily implemented in the numerical models developed to simulate the formation of the SSS.

Keywords: Solar physics
Twenty Years of SpeX: Accuracy Limits of Spectral Slope Measurements in Asteroid Spectroscopy. We examined two decades of SpeX/NASA Infrared Telescope Facility observations from the Small Main-Belt Asteroid Spectroscopic Survey (SMASS) and the MIT-Hawaii Near-Earth Object Spectroscopic Survey (MITHNEOS) to investigate uncertainties and systematic errors in reflectance spectral slope measurements of asteroids. From 628 spectra of 11 solar analogs used for calibration of the asteroid spectra, we derived an uncertainty of on slope measurements over 0.8-2.4 μm. Air mass contributes to -0.92% μm-1 per 0.1 unit air mass difference between the asteroid and the solar analog and therefore for an overall 2.8% μm-1 slope variability in SMASS and MITHNEOS designed to operate within 1.0-1.3 air mass. No additional observing conditions (including the parallactic angle, seeing, and humidity) were found to contribute systematically to slope change. We discuss implications for asteroid taxonomic classification works. Uncertainties provided in this study should be accounted for in future compositional investigation of small bodies to distinguish intrinsic heterogeneities from possible instrumental effects.

Keywords: Near-Earth objects, Small Solar System bodies, Main belt asteroids, Astronomical instrumentation, Spectroscopy
A Flexible Method for Estimating Luminosity Functions via Kernel Density Estimation. We propose a flexible method for estimating luminosity functions (LFs) based on kernel density estimation (KDE), the most popular nonparametric density estimation approach developed in modern statistics, to overcome issues surrounding the binning of LFs. One challenge in applying KDE to LFs is how to treat the boundary bias problem, as astronomical surveys usually obtain truncated samples predominantly due to the flux-density limits of surveys. We use two solutions, the transformation KDE method ( ${\hat{\phi }}_{{\rm{t}}}$ ) and the transformation-reflection KDE method ( ${\hat{\phi }}_{\mathrm{tr}}$ ) to reduce the boundary bias. We develop a new likelihood cross-validation criterion for selecting optimal bandwidths, based on which the posterior probability distribution of the bandwidth and transformation parameters for ${\hat{\phi }}_{{\rm{t}}}$ and ${\hat{\phi }}_{\mathrm{tr}}$ are derived within a Markov Chain Monte Carlo sampling procedure. The simulation result shows that ${\hat{\phi }}_{{\rm{t}}}$ and ${\hat{\phi }}_{\mathrm{tr}}$ perform better than the traditional binning method, especially in the sparse data regime around the flux limit of a survey or at the bright end of the LF. To further improve the performance of our KDE methods, we develop the transformation-reflection adaptive KDE approach ( ${\hat{\phi }}_{\mathrm{tra}}$ ). Monte Carlo simulations suggest that it has good stability and reliability in performance, and is around an order of magnitude more accurate than using the binning method. By applying our adaptive KDE method to a quasar sample, we find that it achieves estimates comparable to the rigorous determination in a previous work, while making far fewer assumptions about the LF. The KDE method we develop has the advantages of both parametric and nonparametric methods.

Keywords: Luminosity function, Smoothing, Bayesian statistics, Astrostatistics techniques, Markov chain Monte Carlo
The PDFI_SS Electric Field Inversion Software. We describe the PDFI_SS software library, which is designed to find the electric field at the Sun's photosphere from a sequence of vector magnetogram and Doppler velocity measurements and estimates of horizontal velocities obtained from local correlation tracking using the recently upgraded Fourier Local Correlation Tracking code. The library, a collection of FORTRAN subroutines, uses the "PDFI" technique described by Kazachenko et al., but modified for use in spherical, Plate Carrée geometry on a staggered grid. The domain over which solutions are found is a subset of the global spherical surface, defined by user-specified limits of colatitude and longitude. Our staggered grid approach, based on that of Yee, is more conservative and self-consistent compared to the centered, Cartesian grid used by Kazachenko et al. The library can be used to compute an end-to-end solution for electric fields from data taken by the HMI instrument aboard NASA's SDO mission. This capability has been incorporated into the HMI pipeline processing system operating at SDO's Joint Science Operations Center. The library is written in a general and modular way so that the calculations can be customized to modify or delete electric field contributions, or used with other data sets. Other applications include "nudging" numerical models of the solar atmosphere to facilitate assimilative simulations. The library includes an ability to compute "global" (whole-Sun) electric field solutions. The library also includes an ability to compute potential magnetic field solutions in spherical coordinates. This distribution includes a number of test programs that allow the user to test the software.

Keywords: Solar active region magnetic fields, Theoretical techniques, Solar photosphere, Space weather, Solar magnetic fields, Solar activity, Active solar corona, Magnetohydrodynamical simulations
Physical and Optical Properties of Ultra-black Nickel-Phosphorus for a Total Solar Irradiance Measurement. The total solar irradiance at the top of the atmosphere is the primary source of energy of the Earth's highly coupled atmosphere-land-ocean system. Small fluctuations of the solar flux density in scales from years to millennia could impact the energy balance of this system due to nonlinear effects. The quantification of this variability depends on absolute radiometers on board of space-based platforms. Although there has been significant improvement in the design and calibration of absolute radiometers during the last decades, the uncertainties in the measurements have not allowed us to untangle the natural and anthropogenic drivers of the observed changes of the climatic patterns appropriately. One of the critical components of the absolute radiometers is the coating of the sensor elements, which should absorb the radiation efficiently. Here we discuss the optical characteristics of ultra-black Nickel-Phosphorus (Ni-P) and its relations with the surface morphology. The ultra-black Ni-P has important unique properties such as low reflectance and uniformity of deposition in complex geometries. Ni-P multilayer was deposited by electroless on aluminum substrates. The surface was etched by oxidizing acid to produce ultra-black Ni-P. Characterization techniques were used to describe the properties of the material. We describe the directional reflectance employing the bidirectional reflectance distribution function. Additionally, we used reflectance maps to show the influence of the pores on the reflectance. Ultra-black Ni-P exhibited a high absorptance and dependence with the light incidence angle. Based on the results, the material demonstrated the opportunity of many terrestrial and space applications as a black coating absorber.

Keywords: Astronomical instrumentation, Telescopes, Solar instruments
Parker Solar Probe Observations of Proton Beams Simultaneous with Ion-scale Waves. Parker Solar Probe (PSP), NASA's latest and closest mission to the Sun, is on a journey to investigate fundamental enigmas of the inner heliosphere. This paper reports initial observations made by the Solar Probe Analyzer for Ions (SPAN-I), one of the instruments in the Solar Wind Electrons Alphas and Protons instrument suite. We address the presence of secondary proton beams in concert with ion-scale waves observed by FIELDS, the electromagnetic fields instrument suite. We show two events from PSP's second orbit that demonstrate signatures consistent with wave-particle interactions. We showcase 3D velocity distribution functions (VDFs) measured by SPAN-I during times of strong wave power at ion scales. From an initial instability analysis, we infer that the VDFs departed far enough away from local thermodynamic equilibrium to provide sufficient free energy to locally generate waves. These events exemplify the types of instabilities that may be present and, as such, may guide future data analysis characterizing and distinguishing between different wave-particle interactions.

Keywords: Space plasmas, Solar wind, Alfven waves, Plasma physics
Clustering of Local Group Distances: Publication Bias or Correlated Measurements? VII. A Distance Framework out to 100 Mpc. We consider the body of published distance moduli to the Fornax and Coma galaxy clusters, with specific emphasis on the period since 1990. We have carefully homogenized our final catalogs of distance moduli onto the distance scale established in the previous papers in this series. We assessed systematic differences associated with the use of specific tracers and consequently discarded results based on application of the Tully-Fisher relation and of globular cluster and planetary nebula luminosity functions. We recommend "best" weighted relative distance moduli for the Fornax and Coma clusters with respect to the Virgo cluster benchmark of ${\rm{\Delta }}(m-M{)}_{0}^{\mathrm{Fornax}-\mathrm{Virgo}}=0.18\pm 0.28$ mag and ${\rm{\Delta }}(m-M{)}_{0}^{\mathrm{Coma}-\mathrm{Virgo}}=3.75\pm 0.23$ mag. The set of weighted mean distance moduli (distances) we derived as most representative of the clusters' distances is m - M0 Fornax = 31.41 ± 0.15 mag (D = 19.1 -1.2 +1.4 Mpc) and = 31.21 ± 0.28 mag (D = 17.5 -2.2 +2.4 Mpc), m - M0 Coma = 34.99 ± 0.38 mag (D = 99.5 -15.9 +19.0 Mpc) and = 34.78 ± 0.27 mag (D = 90.4 -10.6 +11.9 Mpc) where the first distance modulus for each cluster is the result of our analysis of the direct, absolute distance moduli, while the second modulus is based on distance moduli relative to the Virgo cluster. While the absolute and relative distance moduli for both clusters are mutually consistent within the uncertainties, the relative distance moduli yield shorter absolute distances by ∼1σ. It is unclear what may have caused this small difference for both clusters; lingering uncertainties in the underlying absolute distance scale appear to have given rise to a systematic uncertainty of the order of 0.20 mag.

Keywords: Galaxy distances, Astronomy databases, Distance measure, Coma Cluster, Astronomical reference materials
Gamma-Ray Flares in the Long-term Light Curve of 3C 454.3. 3C 454.3 is frequently observed in the flaring state. The long-term light curve of this source has been analyzed with 9 yr (2008 August-2017 July) of data from the Fermi-LAT detector. We have identified five flares and one quiescent state. The flares have substructures with many peaks during the flaring phase. We have estimated the rise and decay time of the flares and compared with flares of other similar sources. The modeling of gamma-ray spectral energy distributions shows in most cases that a log-parabola function gives the best fit to the data. We have done time-dependent leptonic modeling of two of the flares, for which simultaneous multiwavelength data are available. These two long-lasting flares, Flare-2A and Flare-2D, continued for 95 and 133 days, respectively. We have used the average values of Doppler factor, injected luminosity in electrons, size of the emission region, and the magnetic field in the emission region in modeling these flares. The emission region is assumed to be in the broad-line region in our single-zone model. The energy losses (synchrotron, synchrotron self-Compton, external Compton) and escape of electrons from the emission region have been included while doing the modeling. Although the total jet powers required to model these flares with the leptonic model are higher compared to other sources, they are always found to be lower than the Eddington luminosity of 3C 454.3. We also select some flaring peaks and show that the time variation of the Doppler factor or the injected luminosity in electrons over short timescales can explain their light curves.

Keywords: Jets, Quasars, Blazars, Galactic and extragalactic astronomy, Active galactic nuclei, Extragalactic astronomy
MARVEL Analysis of the Measured High-resolution Rovibronic Spectra of the Calcium Monohydroxide Radical (CaOH). The calcium monohydroxide radical (CaOH) is an important astrophysical molecule relevant to cool stars and rocky exoplanets, among other astronomical environments. Here, we present a consistent set of highly accurate rovibronic (rotation-vibration-electronic) energy levels for the five lowest electronic states ( $\tilde{X}{}^{2}{{\rm{\Sigma }}}^{+}$ , $\tilde{A}{}^{2}{\rm{\Pi }}$ , $\tilde{B}{}^{2}{{\rm{\Sigma }}}^{+}$ , $\tilde{C}{}^{2}{\rm{\Delta }}$ , and $\tilde{D}{}^{2}{{\rm{\Sigma }}}^{+}$ ) of CaOH. A comprehensive analysis of the published spectroscopic literature on this system has allowed 1955 energy levels to be determined from 3204 rovibronic experimental transitions, all with unique quantum number labeling and measurement uncertainties. The data set covers rotational excitation up to J = 62.5 for molecular states below 29,000 cm-1. The analysis was performed using the Measured Active Rotational-Vibrational Energy Levels algorithm, which is a robust procedure based on the theory of spectroscopic networks. The data set provided will significantly aid future interstellar, circumstellar, and atmospheric detections of CaOH, as well as assist in the design of efficient laser cooling schemes in ultracold molecule research and precision tests of fundamental physics.

Keywords: Molecular spectroscopy, Astronomy databases, Exoplanet atmospheres
Hyperfine Structure Constants for Levels of <SUP>175</SUP>Lu<SUP>+</SUP>. Accurate and complete atomic data are required for the determination of accurate stellar photospheric abundances. This includes hyperfine structure (HFS) for some elements—those with high nuclear spin and/or large nuclear magnetic moments. Lutetium is one such element. In this study, spectra of a commercial Lu-Ne hollow cathode lamp operating at a low current were recorded with the high-resolution University of Wisconsin 3 m focal length echelle spectrograph. These spectra of resolved and partially resolved hyperfine patterns for 35 ultraviolet and blue transitions of Lu II have been studied for the purpose of extracting hyperfine constants. We present HFS constants for 16 levels of singly ionized lutetium, 10 of which have been measured for the first time.

Keywords: Atomic spectroscopy, Laboratory astrophysics, Stellar abundances