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1211. Atlas of Radio/X-Ray Associations (ARXA)
ID:
ivo://nasa.heasarc/arxa
Title:
Atlas of Radio/X-Ray Associations (ARXA)
Short Name:
ARXA
Date:
21 Feb 2025
Publisher:
NASA/GSFC HEASARC
Description:
The Atlas of Radio/X-Ray Associations (ARXA) is a compendium of all cataloged or APM/USNO-A optical objects which are found to be associated with XMM-Newton, Chandra, RASS, HRI, PSPC or WGACAT X-ray detections, or with NVSS, FIRST or SUMSS radio detections. All detections are listed, plus double radio lobes where found. The source number counts are: <pre> Optical objects - 602,570. NVSS - 266,148 core associations, plus 8309 double lobes. FIRST - 173,383 core associations, plus 12,844 double lobes. SUMSS - 59,138 core associations, plus 2529 double lobes. XMM associations - 57,778. Chandra associations - 32,951. ROSAT RASS - 47,486. ROSAT HRI - 15,523. ROSAT PSPC - 35,607. WGA - 24,226. </pre> Each optical object is given as one entry in this catalog, containing the sky coordinates, the object name (from the literature where available), APM and USNO-A sourced red and blue photometry, redshift, the source catalogs for the name and redshift, the calculated odds that the object is a quasar, galaxy, star, or erroneous association, and the radio & X-ray identifiers, up to 10 of them possible although usually just 1 or 2. This catalog supersedes the previous similar compilation by the same author, the Quasars.org (QORG) Catalog, called QORGCAT in the HEASARC's Browse (see <a href="http://quasars.org/qorg-data.htm">http://quasars.org/qorg-data.htm</a>). Questions or comments on ARXA may be directed to eric@flesch.org. See also: <pre> APM home page <a href="http://www.ast.cam.ac.uk/~apmcat">http://www.ast.cam.ac.uk/~apmcat</a> USNO-A home page <a href="http://www.nofs.navy.mil/">http://www.nofs.navy.mil/</a> NVSS home page <a href="http://www.cv.nrao.edu/nvss/">http://www.cv.nrao.edu/nvss/</a> FIRST home page <a href="http://sundog.stsci.edu/">http://sundog.stsci.edu/</a> SUMSS home page <a href="http://www.astrop.physics.usyd.edu.au/SUMSS/index.html">http://www.astrop.physics.usyd.edu.au/SUMSS/index.html</a> XMM-Newton home page <a href="http://xmmssc-www.star.le.ac.uk">http://xmmssc-www.star.le.ac.uk</a> HRI & PSPC home page <a href="http://www.mpe.mpg.de/ROSAT/">http://www.mpe.mpg.de/ROSAT/</a> WGA home page <a href="http://wgacat.gsfc.nasa.gov/wgacat/wgacat.html">http://wgacat.gsfc.nasa.gov/wgacat/wgacat.html</a> RASS-FSC home page <a href="http://www.xray.mpe.mpg.de/rosat/survey/rass-fsc">http://www.xray.mpe.mpg.de/rosat/survey/rass-fsc</a> RASS-BSC home page <a href="http://www.xray.mpe.mpg.de/rosat/survey/rass-bsc">http://www.xray.mpe.mpg.de/rosat/survey/rass-bsc</a> Chandra home page <a href="http://chandra.harvard.edu">http://chandra.harvard.edu</a> XAssist home page <a href="http://xassist.pha.jhu.edu/zope/xassist">http://xassist.pha.jhu.edu/zope/xassist</a> (XMMX & CXOX sources are from XAssist) </pre> If using this catalog in published research, please add a small mention in the acknowledgements. This table is based on research which made use of the NASA/IPAC Extragalactic Database (NED) operated by the Jet Propulsion Laboratory, California Institute of Technology, under contract with NASA. This online catalog was created by the HEASARC in January 2010 based on a machine-readable table obtained from the author's ARXA web site at <a href="http://quasars.org/arxa.htm">http://quasars.org/arxa.htm</a>. This is a service provided by NASA HEASARC .
1212. Atlas of Stellar Spectra
ID:
ivo://CDS.VizieR/III/44
Title:
Atlas of Stellar Spectra
Short Name:
III/44
Date:
21 Oct 2021
Publisher:
CDS
Description:
There are exactly 8192 spectral elements (points) in each spectrum, regularly spaced in terms of frequency. The first point corresponds to spectral frequency 0, while point number 8193 (not included) corresponds to the laser frequency. The 632.8nm laser frequency was doubled, producing an effective laser wavelength of about 316.4nm. Tentatively, it may be assumed that the exact laser wavelength is 316.43nm. The spectra have been normalized so that the bluest stars are approximately level from 480 to 1000nm. The spectra are linear in intensity with zero intensity at tabulated zero. It was not possible to make satisfactory atmospheric extinction corrections throughout all of the atmospheric bands; at places where corrections could not be made, the spectra were set (exactly) to zero. Some of these spectra have been published already (H.L. Johnson, Rev. Mex. Astron. Astrof. 2, 71, 1977); the remainder will be published soon (Rev. Mex. Astron. Astrofis., 4, 3). These published spectral plots contain in graphical form the information needed to evaluate the signal-to-noise ratios of the spectra on this tape. (From Harold L. Johnson, Dec. 13, 1977)
1213. Atlas of Virgo galaxies
ID:
ivo://CDS.VizieR/VII/266
Title:
Atlas of Virgo galaxies
Short Name:
VII/266
Date:
21 Oct 2021
Publisher:
CDS
Description:
This database contains surface brightness profiles in the optical g, r, i, z bands and near-IR H-band for 286 Virgo cluster galaxies. This morphologically-complete sample spans a huge range in galaxy size, luminosity, surface brightness and stellar populations. These data have been used to study the luminosity and surface brightness distribution of Virgo cluster galaxies, in McDonald et al. (2009MNRAS.394.2022M). We find compelling evidence for bimodal populations in surface brightness, with both early- and late-type galaxies having a dearth of intermediate surface brightness galaxies. Most convincing is our confirmation of the result by Tully and Verheijen that the surface brightness of galaxy disks are strongly bimodal (1997ApJ...484..145T) The near-IR H-band data have been obtained from a variety of telescopes. We downloaded archival images for 31/286 and 84/286 bright galaxies from the 2MASS and GOLDMine online databases, respectively. The remaining 171 galaxies have new observations from the UH 2.2-m (130/286), CFHT (20/286) and UKIRT (21/286) telescopes. These data were all reduced in a homogeneous way, as outlined in our data paper. The optical g, r, i, z data were all obtained from the SDSS archives. Surface brightness profiles were extracted homogeneously from the optical and near-IR data following similar procedures, as outlined in our paper (2011MNRAS.414.2055M) The parametric and non-parametric parameters from bulge-disk decompositions of 285 optical griz and near-IR H-band surface brightness (SB) profiles are given in the bdd_* files in this directory. The profiles are stored in the "prof_g", "prof_r", "prof_i", "prof_z" and "prof_h" subdirectories, one for each color.
1214. Atlas of warm AGN and starbursts
ID:
ivo://CDS.VizieR/J/ApJS/158/139
Title:
Atlas of warm AGN and starbursts
Short Name:
J/ApJS/158/139
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a set of 180 active galactic nucleus (AGN) candidates based on color selection from the IRAS slow-scan deep observations, with color criteria broadened from the initial Point Source Catalog (Cat. <II/125>) samples so as to include similar objects with redshifts up to z=1 and allowing for two-band detections. Spectroscopic identifications have been obtained for 80 (44%); some additional identifications are secure based on radio detections or optical morphology, although yet unobserved spectroscopically. These spectroscopic identifications include 13 type-1 Seyfert galaxies, 17 type-2 Seyferts, 29 starburst galaxies, 7 LINER systems, and 13 emission-line galaxies so heavily reddened as to remain of ambiguous classification.
1215. ATLAS radio observations of ELAIS-S1
ID:
ivo://CDS.VizieR/J/AJ/135/1276
Title:
ATLAS radio observations of ELAIS-S1
Short Name:
J/AJ/135/1276
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have conducted sensitive (1{sigma}<30uJy) 1.4GHz radio observations with the Australia Telescope Compact Array of a field largely coincident with infrared observations of the Spitzer Wide-Area Extragalactic Survey (SWIRE, 2003PASP..115..897L). The field is centered on the European Large Area ISO Survey S1 region and has a total area of 3.9{deg}. We describe the observations and calibration, source extraction, and cross-matching to infrared sources. Two catalogs are presented: one of the radio components found in the image and another of radio sources with counterparts in the infrared and extracted from the literature. 1366 radio components were grouped into 1276 sources, 1183 of which were matched to infrared sources. We discover 31 radio sources with no infrared counterpart at all, adding to the class of Infrared-Faint Radio Sources.
1216. Atmosphere parameters model-derived for PMS & BDs
ID:
ivo://CDS.VizieR/J/ApJ/805/57
Title:
Atmosphere parameters model-derived for PMS & BDs
Short Name:
J/ApJ/805/57
Date:
21 Oct 2021
Publisher:
CDS
Description:
We test state-of-the-art model atmospheres for young very-low-mass stars and brown dwarfs in the infrared, by comparing the predicted synthetic photometry over 1.2-24{mu}m to the observed photometry of M-type spectral templates in star-forming regions. We find that (1) in both early and late young M types, the model atmospheres imply effective temperatures (Teff) several hundred Kelvin lower than predicted by the standard pre-main sequence (PMS) spectral type-Teff conversion scale (based on theoretical evolutionary models). It is only in the mid-M types that the two temperature estimates agree. (2) The Teff discrepancy in the early M types (corresponding to stellar masses >~0.4M_{sun}_ at ages of a few Myr) probably arises from remaining uncertainties in the treatment of atmospheric convection within the atmospheric models, whereas in the late M types it is likely due to an underestimation of dust opacity. (3) The empirical and model-atmosphere J-band bolometric corrections are both roughly flat, and similar to each other, over the M-type Teff range. Thus the model atmospheres yield reasonably accurate bolometric luminosities (Lbol), but lead to underestimations of mass and age relative to evolutionary expectations (especially in the late M types) due to lower Teff. We demonstrate this for a large sample of young Cha I and Taurus sources. (4) The trends in the atmospheric model J-K_s_ colors, and their deviations from the data, are similar at PMS and main sequence ages, suggesting that the model dust opacity errors we postulate here for young ages also apply at field ages.
1217. Atmospheric param. & abundances of red giants
ID:
ivo://CDS.VizieR/J/A+A/616/A112
Title:
Atmospheric param. & abundances of red giants
Short Name:
J/A+A/616/A112
Date:
21 Oct 2021
Publisher:
CDS
Description:
Recent observational results have demonstrated an increase in the surface Na abundance that correlates with stellar mass for red giants between 2 and 3M_{sun}_. This trend supports evolutionary mixing processes as the explanation for Na overabundances seen in some red giants. In this same mass range, the surface Al abundance was shown to be constant. Our main aim was to extend the investigation of the Na and Al surface abundances to giants more massive than 3M_{sun}_. We sought to establish accurately whether the Na abundances keep increasing with stellar mass or a plateau is reached. In addition, we investigated whether mixing can affect the surface abundance of Al in giants more massive than 3M_{sun}_. We obtained new high-resolution spectra of 20 giants in the field of 10 open clusters; 17 of these stars were found to be members of 9 clusters. The giants have masses between 2.5M_{sun}_ and 5.6M_{sun}_. A model atmosphere analysis was performed and abundances of up to 22 elements were derived using equivalent widths. Additionally, abundances of C, N, and O were determined using spectrum synthesis. The abundances of Na and Al were corrected for non-local thermodynamic equilibrium (non-LTE) effects. Moreover, to extend the mass range of our sample, we collected from the literature high-quality C, N, O, and Na abundances of 32 Galactic Cepheids with accurate masses in the range between 3M_{sun}_ and 14M_{sun}_. The surface abundances of C, N, O, Na, and Al were compared to predictions of stellar evolution models with and without the inclusion of rotation-induced mixing. The surface abundances of most giants and Cepheids of the sample can be explained by models without rotation. For giants above ~2.5M_{sun}_, the Na abundances reach a plateau level of about [Na/Fe]~0.20-0.25dex (in non-LTE). This is true for both Cepheids and giants in open clusters. Regarding Al, the non-LTE [Al/Fe] ratios are mostly close to solar and suggest that Al is not affected by the first dredge-up up to ~5.0M_{sun}_. Our results support previous works that found models with rotation to overestimate the mixing effects in intermediate-mass stars.
1218. Atmospheric parameters for nearby B-F stars
ID:
ivo://CDS.VizieR/J/ApJ/804/146
Title:
Atmospheric parameters for nearby B-F stars
Short Name:
J/ApJ/804/146
Date:
21 Oct 2021
Publisher:
CDS
Description:
Age determination is undertaken for nearby early type (BAF) stars, which constitute attractive targets for high-contrast debris disk and planet imaging surveys. Our analysis sequence consists of acquisition of ubvy{beta} photometry from catalogs, correction for the effects of extinction, interpolation of the photometry onto model atmosphere grids from which atmospheric parameters are determined, and finally, comparison to the theoretical isochrones from pre-main sequence through post-main sequence stellar evolution models, accounting for the effects of stellar rotation. We calibrate and validate our methods at the atmospheric parameter stage by comparing our results to fundamentally determined T_eff_ and log g values. We validate and test our methods at the evolutionary model stage by comparing our results on ages to the accepted ages of several benchmark open clusters (IC2602, {alpha} Persei, Pleiades, Hyades). Finally, we apply our methods to estimate stellar ages for 3493 field stars, including several with directly imaged exoplanet candidates.
1219. Atmospheric parameters for 771 stars
ID:
ivo://CDS.VizieR/J/other/RAA/11.924
Title:
Atmospheric parameters for 771 stars
Short Name:
J/other/RAA/11.9
Date:
21 Oct 2021
Publisher:
CDS
Description:
A number of spectroscopic surveys have been carried out or are planned to study the origin of the Milky Way. Their exploitation requires reliable automated methods and softwares to measure the fundamental parameters of the stars. Adopting the ULySS package, we have tested the effect of different resolutions and signal-to-noise ratios (SNR) on the measurement of the stellar atmospheric parameters (effective temperature Teff, surface gravity logg, and metallicity [Fe/H]). We show that ULySS is reliable to determine these parameters with medium-resolution spectra (R~2000). Then, we applied the method to measure the parameters of 771 stars selected in the commissioning database of the Guoshoujing Telescope (GSJT). The results were compared with the SDSS/SEGUE Stellar Parameter Pipeline (SSPP), and we derived precisions of 167K, 0.34dex, and 0.16dex for Teff, logg and [Fe/H] respectively. Furthermore, 120 of these stars are selected to construct the primary stellar spectra template library (Version 1.0) of GSJT, and will be deployed as basic ingredients for the GSJT automated parametrization pipeline.
1220. Atmospheric parameters for 1273 stars
ID:
ivo://CDS.VizieR/J/A+A/525/A71
Title:
Atmospheric parameters for 1273 stars
Short Name:
J/A+A/525/A71
Date:
21 Oct 2021
Publisher:
CDS
Description:
Empirical libraries of stellar spectra play an important role in different fields. For example, they are used as reference for the automatic determination of atmospheric parameters, or for building synthetic stellar populations to study galaxies. The CFLIB (Coude-feed library, Indo-US) database is at present one of the most complete libraries, in terms of its coverage of the atmospheric parameters space (Teff, logg and [Fe/H]) and wavelength coverage 3460-9464{AA} at a resolution of ~1{AA} FWHM. Although the atmospheric parameters of most of the stars were determined from detailed analyses of high-resolution spectra, for nearly 300 of the 1273 stars of the library at least one of the three parameters is missing. For the others, the measurements, compiled from the literature, are inhomogeneous. In this paper, we re-determine the atmospheric parameters, directly using the CFLIB spectra, and compare them to the previous studies. Methods. We use the ULySS program to derive the atmospheric parameters, using the ELODIE library as a reference. Based on comparisons with several previous studies we conclude that our determinations are unbiased. For the 958 F,G, and K type stars the precision on Teff, logg, and [Fe/H] is respectively 43K, 0.13dex and 0.05dex. For the 53 M stars they are 82K, 0.22dex and 0.28dex. And for the 260 OBA type stars the relative precision on Teff is 5.1%, and on logg, and [Fe/H] the precision is respectively 0.19 dex and 0.16 dex. These parameters will be used to re-calibrate the CFLIB fluxes and to produce synthetic spectra of stellar populations.

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