- ID:
- ivo://nasa.heasarc/uvotbscat
- Title:
- UVOT Bright Star Catalog
- Short Name:
- UVOTBSCAT
- Date:
- 07 Mar 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This catalog was compiled from 4 catalogs: Tycho-2, GVCS III, NGC, and the Yale Bright Star Catalog. All catalogs were preprocessed before compiling this catalog to achieve uniform columns and units. Next, they were merged into one catalogue before eliminating "red" objects and precessing all coordinates to epoch 2000.0. The catalog was then corrected for missing decimal points. Finally, the catalog was sorted by R.A. for ease of locating objects within the catalogue. The original catalog contained 239,853 objects brighter than 12.0 mags. This table was originally created by the HEASARC in July 2008 based on an input table supplied by the Swift Project which was compiled by Elizabeth Auden at MSSL. It was renamed to UVOTBSCAT in January 2009. This is a service provided by NASA HEASARC .
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- ID:
- ivo://nasa.heasarc/mdwf10pcux
- Title:
- UV/X-Ray Data for M Dwarfs Within 10 Parsecs
- Short Name:
- MDWF10PCUX
- Date:
- 07 Mar 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- M dwarfs are the most numerous stars in the galaxy. They are characterized by strong magnetic activity. The ensuing high-energy emission is crucial for the evolution of their planets and the eventual presence of life on them. The authors systematically study the X-ray and ultraviolet emission of a subsample of M dwarfs from a recent proper-motion survey, selecting all M dwarfs within 10 pc to obtain a nearly volume-limited sample (~90% completeness). Archival ROSAT, XMM-Newton and GALEX data are combined with published spectroscopic studies of H-alpha emission and rotation to obtain a broad picture of stellar activity on M dwarfs. The authors make use of synthetic model spectra to determine the relative contributions of photospheric and chromospheric emission to the ultraviolet flux. They also analyze the same diagnostics for a comparison sample of young M dwarfs in the TW Hya association (~10 Myr old). The authors find that generally the emission in the GALEX bands is dominated by the chromosphere but the photospheric component is not negligible in early-M field dwarfs. The surface fluxes for the H-alpha, near-ultraviolet, far-ultraviolet and X-ray emission are connected via a power-law dependence. The authors present in the reference paper for the first time such flux-flux relations involving broad-band ultraviolet emission for M dwarfs. Activity indices are defined as the flux ratios between the activity diagnostics and the bolometric flux of the star in analogy to the Ca II R'(HK) index. For a given spectral type, these indices display a spread of 2-3 dex which is largest for M4-type stars. Strikingly, at mid-M spectral types, the spread of rotation rates is also at its highest level. The mean activity index for fast rotators, likely representing the saturation level, decreases from X-rays over the FUV to the NUV band and H-alpha, i.e. the fractional radiation output increases with atmospheric height. The comparison to the ultraviolet and X-ray properties of TW Hya members shows a drop of nearly three orders of magnitude for the luminosity in these bands between ~10 Myr and a few Gyr age. A few young field dwarfs (<1 Gyr) in the 10-pc sample bridge the gap indicating that the drop in magnetic activity with age is a continuous process. The slope of the age decay is steeper for the X-ray than for the UV luminosity. This sample is based on the All-Sky Catalog of bright M dwarfs published by Lepine & Gaidos (2011, AJ, 142, 138, <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/AJ/142/138">CDS Cat. J/AJ/142/138</a>, available at the HEASARC as the MDWARFASC table). The authors selected all 163 stars from this reference that are within 10pc. Four of these stars that were discovered to be actually late K-type stars were removed from this initial sample, leaving a final sample of 159 stars. This table was created by the HEASARC in July 2017 based upon <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/MNRAS/431/2063">CDS Catalog J/MNRAS/431/2063</a> files table1.dat and table2.dat. The positions of the stars were not explicitly given in these tables, but were taken by the HEASARC from the All-Sky Catalog of Bright M Dwarfs published by Lepine & Gaidos (2011, AJ, 142, 138, <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/AJ/142/138">CDS Cat. J/AJ/142/138</a>, available at the HEASARC as the MDWARFASC table). The version of Table 2 used by the HEASARC is the corrected one given in the Erratum (Stelzer et al. 2014) rather than the version given in the original paper (Stelzer et al. 2013). This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/vela5b
- Title:
- Vela 5B All-Sky Monitor Lightcurves
- Short Name:
- VELA5B
- Date:
- 07 Mar 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- Data for these sources were obtained from the Vela 5B all-sky XC detector. The Vela 5B nuclear test detection satellite was part of a program run jointly by the Advanced Research Projects of the U.S. Department of Defense and the U.S.Atomic Energy Commission, managed by the U.S. Air Force. It was placed in a nearly circular orbit at a geocentric distance of ~118,000 km on 23 May 1969; the orbital period was ~112 hours. The satellite rotated about its spin axis with a ~64-sec period. The X-ray detector was located ~90 degrees from the spin axis, and so covered the celestial sphere twice per satellite orbit. Data were telemetered in 1-sec count accumulations. Vela 5B operated until 19 June 1979, although telemetry tracking was poor after mid-1976. The scintillation X-ray detector (XC) aboard Vela 5B consisted of two 1-mm-thick NaI(Tl) crystals mounted on photomultiplier tubes and covered by a 5-mil-thick beryllium window. Electronic thresholds provided two energy channels, 3-12 keV and 6-12 keV. In front of each crystal was a slat collimator providing a FWHM aperture of ~6.1x6.1 degrees. The effective detector area was ~26 sq-cm. Sensitivity to celestial sources was severely limited by the intrinsic detector background of ~36 cts/sec. The Vela 5B X-ray detector yielded ~40 cts/sec for the Crab, so 1 Vela ct/sec ~25 UFU~4.5E-10 ergs/sq-cm/sec in the 3-12 keV response band. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/konus
- Title:
- VeneraKONUS11&12Bursts
- Short Name:
- KONUS
- Date:
- 07 Mar 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The KONUS instruments were flown on pairs of Venera spacecraft. Veneras 11/12 were launched in September 1978; bursts were recorded through January 1980. Veneras 13/14 were launched in November 1981 and were operational through approximately March 1983. The Veneras were interplanetary spacecraft, which flew to Venus, and thus each spacecraft had whole sky coverage for most of its mission. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/verimaster
- Title:
- VERITAS Source Catalog
- Short Name:
- VERIMASTER
- Date:
- 07 Mar 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The Very Energetic Radiation Imaging Telescope Array System (VERITAS) is a major ground-based gamma-ray observatory operating at the Fred Lawrence Whipple Observatory (FLWO) in southern Arizona, USA. It is an array of four 12m optical telescopes for gamma-ray astronomy in the GeV - TeV energy range. VERITAS is an imaging air Cerenkov system. Gamma-rays from astrophysical sources create particle showers in the Earth's upper atmosphere that produce Cerenkov photons detected on the ground using the large optical telescopes. These telescopes are deployed such that they have the highest sensitivity in the VHE energy band (50 GeV - 50 TeV), with maximum sensitivity from 100 GeV to 10 TeV. The four telescope array is needed for stereoscopic observations that allow the reconstruction of the particle shower geometry, thus giving precise angular and energy resolution. This very high energy observatory, completed in 2007, effectively complements the Fermi Gamma-ray Space Telescope due to its large collection area as well as its higher energy bound and improved angular resolution. VERITAS started four-telescope operations in 2007 and collects about 1100 hours of good-weather data per year. The VERITAS collaboration has published over 100 journal articles since 2008 reporting on gamma-ray observations of a large variety of objects: Galactic sources like supernova remnants, pulsar wind nebulae, and binary systems; extragalactic sources like star forming galaxies, dwarf-spheroidal galaxies, and highly-variable active galactic nuclei. Additional details are available at the <a href="https://veritas.sao.arizona.edu/">VERITAS website</a>. The catalog lists the sources observed by VERITAS as of April 2022, including cross-matches with other gamma-ray observations and spectral fits. This catalog has associated high-level data products containing data from VERITAS publications. This database table was ingested by the HEASARC in December 2022 and is based upon data files provided by the VERITAS Team. A minor correction to one entry in the catalog was made in April 2024. <p> High-level data products were collected from VERITAS publications. Data and fit results were extracted from the published papers or from internal VERITAS analysis results used to produce the published figures and tables. In many cases, spectral and light curve data were obtained by digitizing published figures. This process was led by Gernot Maier at DESY with contributions from many members of the VERITAS collaboration. The primary archive can be accessed on <a href="https://github.com/VERITAS-Observatory/VERITAS-VTSCat">GitHub</a> or downloaded via Zenodo (doi:10.5281/zenodo.6163391). Translation to formats suitable for the HEASARC was led by Philip Kaaret with assistance by Sameer Patel at the University of Iowa and by the HEASARC Team. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/veroncat
- Title:
- VeronCatalogofQuasars&AGN,13thEdition
- Short Name:
- Veron
- Date:
- 07 Mar 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This database table contains the 13th edition of the Catalog of Quasars and Active Galactic Nuclei by Veron-Cetty and Veron, and is an update of the previous versions. As in the previous editions, no information about absorption lines or X-ray properties is given, but absolute magnitides are provided, assuming a Hubble constant H<sub>0</sub> = 71 km/s/Mpc and a deceleration parameter q<sub>0</sub> = 0 (notice the change of cosmology from previous editions in which H<sub>0</sub> was assumed to be 50 km/s/Mpc). The present edition of this catalog contains 133336 quasars, 1374 BL Lac objects and 34231 active galaxies (including 15627 Seyfert 1 galaxies), for a grand total of 168941 objects, significantly more than the number of objects listed in the 12th edition (108080). The 13th edition includes positions and redshifts, as well as photometry (U, B, and V) and 6-cm and 20-cm flux densities, when available. 178 objects once proposed but now rejected as quasars are NOT included in the online version of this catalog: their names and positions are listed in the file <a href="https://cdsarc.cds.unistra.fr/ftp/cats/VII/258/reject.dat">https://cdsarc.cds.unistra.fr/ftp/cats/VII/258/reject.dat</a>. This HEASARC table also does NOT contain the additional information on gravitationally lensed quasars and quasar pairs listed in Tables 3 and 4 of the published paper: these tables are available in electronic form at the CDS <a href="https://cdsarc.cds.unistra.fr/ftp/cats/VII/248/">https://cdsarc.cds.unistra.fr/ftp/cats/VII/248/</a> files table2.dat and table3.dat (sic). The present edition of this catalog contains quasars with measured redshift known prior to July 1st, 2009. This online catalog was created by the HEASARC in April 2010 based on machine-readable tables obtained from the CDS (their catalog VII/258, files qso.dat, bllac.dat, and agn.dat). It was last updated in June 2012 to tweak some class values. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/vla23901p4
- Title:
- VLA A2390 Cluster of Galaxies 1.4-GHz Source Catalog
- Short Name:
- VLA23901P4
- Date:
- 07 Mar 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains the 1.4-GHz source catalog for the field of the cluster of galaxies A2390 as observed with the Very Large Array (VLA). This is one of the deepest radio images of a cluster field ever taken. The image covers an area of 34' x 34' with a synthesized beam of ~1.4" and a noise level of ~5.6 µJy (µJy) near the field center. In the reference paper, the authors construct differential number counts for the central regions (radius < 16') of this cluster, and find that the faint (S<sub>1.4GHz</sub> < 3 mJy) counts of A2390 are roughly consistent with the lowest blank field number counts. Their analyses indicate that the number counts are primarily from field radio galaxies. The authors suggest that the disagreement of their number counts for this cluster with those from a similarly deep observation of A370 that was also presented in the reference paper can be largely attributed to cosmic variance. The authors observed the A2390 cluster field with the VLA in the A configuration for ~31.4hr on-source during 2008 October. The field center is located at 21:53:36 +17:41:52 (J2000). This table was created by the HEASARC in August 2017 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/ApJS/202/2/">CDS Catalog J/ApJS/202/2/</a> file table2.dat. This file contained 699 entries for sources detected at 1.4 GHz in the A370 field, as well as 524 entries for sources detected at 1.4 GHz in the A2390 field. Only the latter are included in this HEASARC table, while the former can be found in the HEASARC's <a href="vla3701p4.html">VLA3701P4</a> table. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/vla3701p4
- Title:
- VLA A370 Cluster of Galaxies 1.4-GHz Source Catalog
- Short Name:
- VLA3701P4
- Date:
- 07 Mar 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains the 1.4-GHz source catalog for the field of the cluster of galaxies A370 as observed with the Very Large Array (VLA). This is one of the deepest radio images of a cluster field ever taken. The image covers an area of 40' x 40' with a synthesized beam of ~1.7" and a noise level of ~5.7 µJy (µJy) near the field center. The authors have cataloged 200 redshifts for the A370 field. In the reference paper, they construct differential number counts for the central regions (radius < 16') of this cluster, and find that the faint (S<sub>1.4GHz</sub> < 3 mJy) counts of A370 are roughly consistent with the highest blank field number counts. Their analyses indicate that the number counts are primarily from field radio galaxies. The authors suggest that the disagreement of their number counts for this cluster with those from a similarly deep observation of A2390 that was also presented in the reference paper can be largely attributed to cosmic variance. The authors observed the A370 cluster field with the VLA in the A configuration for ~42.4hr on-source during 1999 August and September. K. S. Dwarakanath observed A370 in the B configuration for ~18.4hr on-source during 1994 August and September. The field center is located at 02:39:32 -01:35:07 (J2000). This is offset by approximately 5 arcminutes from the cluster center at 02:39:50.5 -01:35:08. The authors also targeted 58 radio sources, in A370, that had no existing optical spectral data using the Hydra fiber spectrograph on the Wisconsin-Indiana-Yale-NOAO (WIYN) telescope (spectral window of ~4500 - 9500 Angstrom). They preferentially targeted optically bright galaxies, obtaining these data in a single two-hour pointing on 2012 January 20. Of the 58 targets, the authors obtained high-confidence redshifts for 36. This table was created by the HEASARC in August 2017 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/ApJS/202/2/">CDS Catalog J/ApJS/202/2/</a> file table2.dat. This file contained 699 entries for sources detected at 1.4 GHz in the A370 field, as well as 524 entries for sources detected at 1.4 GHz in the A2390 field. Only the former are included in this HEASARC table, while the latter can be found in the HEASARC's <a href="vla23901p4.html">VLA23901P4</a> table. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/vlacomacat
- Title:
- VLA Coma Cluster of Galaxies 1.4-GHz Source Catalog
- Short Name:
- VLACOMACAT
- Date:
- 07 Mar 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains results from deep 1.4-GHz Very Large Array (VLA) radio continuum observations of two ~0.5 deg<sup>2</sup> fields in the Coma cluster of galaxies. The two fields, "Coma 1" and "Coma 3", correspond to the cluster core and the southwest infall region, and were selected on account of abundant pre-existing multiwavelength data. In their most sensitive regions, the radio data reach 0.022 mJy (22 µJy) rms per 4.4" beam, sufficient to detect (at 5-sigma) Coma member galaxies with L<sub>1.4GHz</sub> = 1.3 x 10<sup>20</sup> W Hz<sup>-1</sup> (1.3 x 10<sup>27</sup> erg s<sup>-1</sup> Hz<sup>-1</sup>). The full catalog of radio detections at and above a 4.5-sigma significance threshold is presented herein; there are 1030 of these sources which are detected at >= 5 sigma, 628 of which are within the combined Coma 1 and Coma 3 area. The authors also provide optical identifications of the radio sources using data from the Sloan Digital Sky Survey (SDSS). The depth of the radio observations allows them to detect active galactic nuclei in cluster elliptical galaxies with M<sub>r</sub> < -20.5 (AB magnitudes), including radio detections for all cluster ellipticals with M<sub>r</sub> < -21.8. At fainter optical magnitudes (-20.5 < M<sub>r</sub> <~ -19), the radio sources are associated with star-forming galaxies with star formation rates as low as 0.1M_{sun}_ yr<sup>-1</sup>. The VLA observations were performed over five days in 2006 June as program code AM868. On each of the five days, the scheduled time was centered on the transit of Coma. This table was created by the HEASARC in December 2011 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/AJ/137/4436">CDS catalog J/AJ/137/4436</a> files table2.dat ('The Radio Source Catalog') and table3.dat ('Optical Counterparts to the Radio Sources'). It does not include table4.dat ('Rejected Optical Counterparts to the Radio Sources'). This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/vlacosxoid
- Title:
- VLA-COSMOS 3-GHz Large Project Multiwavelength Counterparts Catalog
- Short Name:
- VLACOSXOID
- Date:
- 07 Mar 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- In the reference paper, the authors study the composition of the faint radio population selected from the VLA-COSMOS 3-GHz Large Project, a radio continuum survey performed at 10-cm wavelength. The survey covers a 2.6 square degree area with a mean rms of ~2.3 µJy/beam (µJy/beam), cataloguing 10,830 sources above 5 sigma, and enclosing the full 2 square degree COSMOS field. By combining these radio data with optical, near-infrared (UltraVISTA), and mid-infrared (Spitzer/IRAC) data, as well as X-ray data (Chandra), the authors find counterparts to radio sources for ~93% of the total radio sample in the unmasked areas of the COSMOS field, i.e., those not affected by saturated or bright sources in the optical to near-IR (NIR) bands, reaching out to z ~ 6. They further classify the sources as star-forming galaxies or AGN based on various criteria, such as X-ray luminosity, observed mid-infrare (MIR) color, UV-far-infrared (FIR) spectral-energy distribution (SED), rest-frame near-ultraviolet (NUV)-optical color corrected for dust extinction, and radio-excess relative to that expected from the the hosts' star-formation rate. The authors separate the AGN into sub-samples dominated by low-to-moderate and moderate-to-high radiative luminosity AGN, i.e., candidates for high-redshift analogs to local low- and high-excitation emission line AGN, respectively. They study the fractional contributions of these sub-populations down to radio flux levels of ~11 uJy at 3 GHz (or ~20 uJy at 1.4 GHz assuming a spectral index of -0.7), and find that the dominant fraction at 1.4 GHz flux densities above ~200 uJy is constituted of low-to-moderate radiative luminosity AGN MLAGN). Below densities of ~100 uJy the fraction of star-forming galaxies (SFG) increases to ~60%, followed by the moderate-to-high radiative luminosity AGN (HLAGN) with ~20%, and MLAGN with ~20%. Based on this observational evidence, the authors extrapolate the fractions down to sensitivities of the Square Kilometer Array (SKA). Their estimates suggest that at the faint flux limits to be reached by the (Wide, Deep, and UltraDeep) SKA1 surveys, a selection based only on radio flux limits can provide a simple tool to efficiently identify samples highly (>75%) dominated by star-forming galaxies. This table contains the full list of 9,161 optical-MIR counterparts collected over the largest unmasked area accessible to each catalog, being 1.77, 1.73, and 2.35 square degrees for COSMOS2015, i-band, and IRAC catalogs, respectively. The catalog lists the counterpart IDs, properties, as well as the individual criteria used in this work to classify these radio sources. The authors note that complete, non-overlapping samples within a well defined, effective area of 1.77 square degrees (COSMOS2015 masked area flag_C15 = 0, can be formed by combining (i) HLAGN, MLAGN, and clean SFG samples, or, alternatively, (ii) the radio-excess and no-radio-excess samples. This table was created by the HEASARC in July 2017 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/A+A/602/A2">CDS Catalog J/A+A/602/A2</a> file table1.dat, the VLA-COSMOS 3-GHz Large Project multiwavelength counterpart catalog. This is a service provided by NASA HEASARC .
