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16421. Unified model of active galactic nuclei
ID:
ivo://CDS.VizieR/J/ApJ/660/1072
Title:
Unified model of active galactic nuclei
Short Name:
J/ApJ/660/1072
Date:
21 Oct 2021
Publisher:
CDS
Description:
We assemble a sample composed of 243 nearby Seyfert galaxies with redshifts z<=0.05 to test the unification scheme. The sample contains 94 broad emission line Seyfert 1 galaxies (BLS1s), 44 narrow emission line Seyfert 1s (NLS1s), 36 X-ray-absorbed hidden broad line region Seyfert 2s (HBLR S2s), 42 X-ray-absorbed non-HBLR S2s, and 27 X-ray-unabsorbed Seyfert 2s (unabsorbed non-HBLR S2s and HBLR S2s). We find that (1) NLS1s have less massive black hole masses than BLS1s, (2) HBLR S2s have the same mass distribution of black holes as BLS1s, (3) absorbed non-HBLR S2s have less massive black holes than HBLR S2s, and (4) unabsorbed non-HBLR S2s have the most massive black holes.
16422. United States Naval Observatory B1.0 Catalog
ID:
ivo://irsa.ipac/USNO/Catalog/USNO-B1
Title:
United States Naval Observatory B1.0 Catalog
Short Name:
USNO-B1
Date:
01 Oct 2018 20:27:21
Publisher:
NASA/IPAC Infrared Science Archive
Description:
This all-sky catalog, described in Monet et al. (2003), consists of positions, proper motions, magnitudes, and other measured quantities for 1,045,175,762 objects. The data were derived from digitizing scans of almost 7,500 photographic plates taken from various sky surveys during the interval from 1949 to 2002. The originating plate material includes five complete coverages of the northern sky and four of the southern sky. To be included in the catalog, an object must have been detected on two different surveys because isolated, single-survey detections are unreliable. For the earlier USNO-A catalog (which was essentially a two-color, one-epoch catalog), this meant that the object must have had detectable fluxes on both the red and blue plates, and this led to the exclusion of many faint objects with non-neutral colors. Also, the larger epoch difference in the southern survey coverage meant that objects with larger proper motions tended to be excluded. USNO-B1.0 attempts to fix both of these problems. An object detected in the same band at two epochs will be included in USNO-B1.0, as will objects that have significant proper motions, although it is still the case that objects with large motions and extreme colors may be omitted. The selection algorithm requires that spatially coincident detections must be made on any two of the surveys for an object to be classified as real and be included in the catalog. The catalog is expected to be complete down to V=21. Estimated positional accuracies are 0.2 arcsec, photographic magnitude accuracies are 0.3 mag, and the accuracy for distinguishing stars from non-stellar objects is 85%.
16423. Universidad Complutense de Madrid list 3
ID:
ivo://CDS.VizieR/J/ApJS/122/415
Title:
Universidad Complutense de Madrid list 3
Short Name:
J/ApJS/122/415
Date:
21 Oct 2021
Publisher:
CDS
Description:
A new low-dispersion objective-prism search for low-redshift (z<0.045) emission-line galaxies (ELGs) has been carried out by the Universidad Complutense de Madrid using the Schmidt Telescope at the Calar-Alto Observatory. This is a continuation of the UCM Survey, which was performed by visual selection of candidates in photographic plates via the presence of the H{alpha}+[N II]{lambda}6584 blend in emission. In making this new list we have applied an automatic procedure, fully developed by us, for selecting and analyzing ELG candidates on the digitized images obtained with the "Machine Automatique a Mesurer pour l'Astronomie" (MAMA). The analyzed region of the sky covers 189deg^2^ in nine fields near RA=14h and 17h, DE=25{deg}. The final sample contains 113 candidates. Special effort has been made to obtain a large amount of information directly from our uncalibrated plates by using several external calibrations. The parameters obtained for the ELG candidates allow us to study the statistical properties of the sample.
16424. Universidad Complutense de Madrid list 2
ID:
ivo://CDS.VizieR/J/ApJS/105/343
Title:
Universidad Complutense de Madrid list 2
Short Name:
J/ApJS/105/343
Date:
21 Oct 2021
Publisher:
CDS
Description:
A low dispersion objective-prism survey for low-redshift emission-line galaxies (ELGs) is being carried out by the University Complutense de Madrid with the Schmidt telescope at the German-Spanish Observatory of Calar Alto (Almeria, Spain). A 4{deg} full aperture prism, which provides a dispersion of 1950{AA}/mm, and IIIa-F emulsion combination has been used to search for ELGs selected by the presence of H{alpha} emission in their spectra. A compilation of descriptions and positions, along with finding charts, is presented for 103 emission-line objects. This is the second list, which contains objects located in a region of the sky covering 201.4{deg}^2^ in seven fields near {alpha}=15h and {delta}=25{deg}.
16425. Universidad Complutense de Madrid list 1
ID:
ivo://CDS.VizieR/J/ApJS/95/387
Title:
Universidad Complutense de Madrid list 1
Short Name:
J/ApJS/95/387
Date:
21 Oct 2021
Publisher:
CDS
Description:
A low dispersion objective-prism survey for low-redshift emission-line galaxies (ELGs) is being carried out by the University Complutense de Madrid with the Schmidt telescope at the German-Spanish Observatory of Calar Alto (Almeria, Spain). A 4deg full aperture prism, which provides a dispersion of 1950A/mm, and IIIa-F emulsion combination has been used to search for ELGs selected by the presence of H{alpha} emission in their spectra. Our survey has proved to be able to recover objects already found by similar surveys with different techniques and, what is more important, to discover new objects not previously catalogued. A compilation of descriptions and positions, along with finding charts when necessary, is presented for 160 extragalactic emission-line objects. This is the first list, which contains objects located in a region of the sky covering 270deg^2^ in 10 fields near {alpha}=0h and {delta}=20deg.
16426. Unknown active galactic nuclei study
ID:
ivo://CDS.VizieR/J/A+A/647/A195
Title:
Unknown active galactic nuclei study
Short Name:
J/A+A/647/A195
Date:
21 Oct 2021
Publisher:
CDS
Description:
We collect data at all frequencies for the new sources classified as unknown active galactic nuclei (AGNs) in the latest Burst Alert Telescope all-sky hard X-ray catalog. Focusing on the 36 sources with measured redshift, we compute their spectral energy distribution (SED) from radio to {gamma}-rays with the aim to classify these objects. We apply emission models that attempt to reproduce the obtained SEDs, including: (i) a standard thin accretion disk together with an obscuring torus and a X-ray corona; (ii) a two temperature thick advection-dominated flow; (iii) an obscured AGN model, accounting for absorption along the line of sight at kiloelectronvolt energies and in the optical band; and (iv) a phenomenological model to describe the jet emission in blazar-like objects. We integrate the models with the SWIRE template libraries to account for the emission of the host galaxy. For every source we found a good agreement between data and our model. Considering that the sources were selected in the hard X-ray band, which is rather unaffected by absorption, we expected and found a large fraction of absorbed radio-quiet AGNs (31 out of 36) and some additional rare radio-loud sources (5 out of 36), since the jet emission in hard X-rays is important for aligned jets owing to the boost produced by the beaming effect. With our work we can confirm the hypothesis that a number of galaxies, whose optical spectra lack AGN emission features, host an obscured active nucleus. The approach we used proved to be efficient in rapidly identifying objects, which commonly used methods were not able to classify.
16427. Unresolved binaries in TESS with speckle imaging
ID:
ivo://CDS.VizieR/J/AJ/157/211
Title:
Unresolved binaries in TESS with speckle imaging
Short Name:
J/AJ/157/211
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Transiting Exoplanet Survey Satellite (TESS) is conducting a two-year wide-field survey searching for transiting exoplanets around nearby bright stars that will be ideal for follow-up characterization. To facilitate studies of planet compositions and atmospheric properties, accurate and precise planetary radii need to be derived from the transit light curves. Since 40%-50% of exoplanet host stars are in multiple star systems, however, the observed transit depth may be diluted by the flux of a companion star, causing the radius of the planet to be underestimated. High angular resolution imaging can detect companion stars that are not resolved in the TESS Input Catalog, or by seeing-limited photometry, to validate exoplanet candidates and derive accurate planetary radii. We examine the population of stellar companions that will be detectable around TESS planet candidate host stars, and those that will remain undetected, by applying the detection limits of speckle imaging to the simulated host star populations of Sullivan et al. (2015, J/ApJ/809/77) and Barclay et al. (2018, J/ApJS/239/2). By detecting companions with contrasts of {Delta}m~<7-9 and separations of ~0.02"-1.2", speckle imaging can detect companion stars as faint as early M stars around A-F stars and stars as faint as mid-M around G-M stars, as well as up to 99% of the expected binary star distribution for systems located within a few hundred parsecs.
16428. Unresolved H{alpha} enhancements in WHAM survey
ID:
ivo://CDS.VizieR/J/AJ/129/927
Title:
Unresolved H{alpha} enhancements in WHAM survey
Short Name:
J/AJ/129/927
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have identified 85 regions of enhanced H{alpha} emission at |b|>10{deg} subtending approximately 1{deg} or less on the Wisconsin H{alpha} Mapper (WHAM) sky survey (Cat. II/249). These high-latitude "WHAM point sources" have H{alpha} fluxes of 10^-11^-10^-9^ergs/cm^2^/s, radial velocities within about 70km/s of the LSR, and line widths that range from less than 20 to about 80km/s (FWHM). Twenty-nine of these enhancements are not identified with either cataloged nebulae or hot stars and appear to have kinematic properties that differ from those observed for planetary nebulae. Another 14 enhancements are near hot evolved low-mass stars that had no previously reported detections of associated nebulosity. The remainder of the enhancements are cataloged planetary nebulae and small, high-latitude HII regions surrounding massive O and early B stars.
16429. UNSW catalog of Variable Stars
ID:
ivo://CDS.VizieR/J/MNRAS/385/1749
Title:
UNSW catalog of Variable Stars
Short Name:
J/MNRAS/385/1749
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a new catalogue of variable stars compiled from the data taken for the University of New South Wales Extrasolar Planet Search. From 2004 October to 2007 May, 25 target fields were each observed for one to four months, resulting in ~87000 high-precision light curves with 16004400 data points. We have extracted a total of 850 variable light curves, 659 of which do not have a counterpart in the General Catalogue of Variable Stars, the New Suspected Variables catalogue or the All Sky Automated Survey southern variable star catalogue. The catalogue is detailed here, and includes 142 Algol-type eclipsing binaries, 23 beta Lyrae-type eclipsing binaries, 218 contact eclipsing binaries, 53 RR Lyrae stars, 26 Cepheid stars, 13 rotationally variable active stars, 153 uncategorized pulsating stars with periods <10d, including delta Scuti stars, and 222 long period variables with variability on time-scales of >10d.
16430. Untangling the Galaxy. II. Structure within 3kpc
ID:
ivo://CDS.VizieR/J/AJ/160/279
Title:
Untangling the Galaxy. II. Structure within 3kpc
Short Name:
J/AJ/160/279
Date:
09 Mar 2022 22:00:00
Publisher:
CDS
Description:
We present the results of the hierarchical clustering analysis of the Gaia DR2 data to search for clusters, comoving groups, and other stellar structures. The current paper builds on the sample from the previous work, extending it in distance from 1 to 3kpc and increasing the number of identified structures up to 8292. To aid in the analysis of the population properties, we developed a neural network called Auriga to robustly estimate the age, extinction, and distance of a stellar group based on the input photometry and parallaxes of the individual members. We apply Auriga to derive the properties of not only the structures found in this paper, but also previously identified open clusters. Through this work, we examine the temporal structure of the spiral arms. Specifically, we find that the Sagittarius Arm has moved by >500pc in the last 100Myr and the Perseus Arm has been experiencing a relative lull in star formation activity over the last 25Myr. We confirm the findings of the previous paper on the transient nature of the spiral arms, with the timescale of transition of a few 100Myr. Finally, we find a peculiar ~1Gyr old stream of stars that appears to be heliocentric. Its origin is unclear.

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