- ID:
- ivo://nasa.heasarc/td1
- Title:
- TD1 Stellar Ultraviolet Fluxes Catalog
- Short Name:
- TD1
- Date:
- 07 Mar 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The Belgian/UK Ultraviolet Sky Survey Telescope (S2/68) in the ESRO TD1 satellite carried out a controlled scan of the entire sky. It measured the absolute ultraviolet flux distribution between 2740A and 1350A of point sources down to 10th visual magnitude for unreddened early B stars. The S2/68 experiment has been described by Boksenberg et al. (1973MNRAS.163..291B), and the absolute calibration by Humphries et al. (1976A&A....49..389H). The TD1 Catalog of Stellar Ultraviolet Fluxes represents results from the sky-scan experiment on the TD1 satellite of the European Space Research Organization (ESRO), now part of ESA. It lists the absolute fluxes, in four passbands, for 31,215 stars: <pre> Passband Center: 274.0nm 236.5nm 196.5nm 156.5nm Effective Width: 31.0nm 33.0nm 33.0nm 33.0nm </pre> The stars have been selected subject to the constraint that the signal-to-noise ratio should be at least 10.0 in any one of the four passbands. Null values of a flux field and an error field indicate there are no valid data for the star. This usually arises with close pairs of stars whose spectra overlap. Five standard flux error values are greater than 99.99, and were too large for the format of the flux field in the original table. Thus, the flux error values which were greater than 99.99 are given as 99.99. Many of the fainter stars of spectral type later than A5 do not have significant signals in all of the spectrophotometric channels (particularly the 1565A channel). Consequently, after the removal of the background, they can randomly give rise to small negative values of flux. Those negative values were not suppressed, but are given together with their error, as they can be significant when considered as part of a statistical sample. Although the sky coverage is essentially complete, the catalog does not contain the fluxes for all stars that fall within the limit of the sensitivity of the instrument. If any star expected to be present is missing, then its signal is probably blended with that of a nearby star, in which case the data have been discarded. The original contents of the HEASARC's TD1 database table came from a magnetic tape sent to NASA/Goddard Space Flight Center by Dr. G.I. Thompson of the Royal Observatory in Edinburgh, Scotland. The HEASARC recreated this database table in August 2005, based on the <a href="https://cdsarc.cds.unistra.fr/ftp/cats/II/59B">CDS Catalog II/59B</a> file catalog.dat.gz, in an effort to modernize its parameter names and documentation, as well as to add Galactic coordinates. The data in the CDS version originally came from "Selected Astronomical Catalogs" Vol. 1 CD-ROM released by the NASA Astronomical Data Center (ADC) in 1991. This is a service provided by NASA HEASARC .
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- ID:
- ivo://nasa.heasarc/tevcat
- Title:
- TeV Gamma-Ray Source Catalog
- Short Name:
- TEVCAT
- Date:
- 07 Mar 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- TeVCat (<a href="http://tevcat.org/">http://tevcat.org/</a>) is an online, interactive catalog for very-high-energy (VHE: energies, E >~ 50 GeV) gamma-ray astronomy. As VHE astronomy continues to grow, the usefulness of a one-stop clearing house for information on new sources is increasingly evident. TeVCat is intended to be such a resource. With sky maps, scientific information, visibility plotters and linked references available at the website, it will help the wider gamma-ray community stay up-to-date and informed on this exciting and rapidly developing field. This HEASARC database table provides the TeVCat list of VHE sources as well as links to the TeV source resource pages on the TeVCat website. The catalog and <a href="http://tevcat.org/">the website at the University of Chicago</a> are maintained by Scott Wakely and Deirdre Horan. This table was first ingested by the HEASARC in July 2017 based on the catalog of VHE gamma-ray sources available at <a href="http://tevcat.org/">http://tevcat.org/</a>. It is updated automatically within a few days of the catalog being updated on the University of Chicago website. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/wrcat
- Title:
- The VIIth Catalog of Galactic Wolf-Rayet Stars
- Short Name:
- WR
- Date:
- 07 Mar 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The VIIth Catalogue of Galactic Population I Wolf-Rayet (WR) Stars provides improved coordinates, spectral types, and bv photometry of known WR stars and adds 71 new stars compared to the VIth Catalog. This census of galactic WR stars has reached 227 stars (226 entries in this catalog), comprising 127 WN stars, 87 WC stars, 10 WN/WC stars, and 3 WO stars. This includes 15 WNL and 11 WCL stars within 30 pc of the Galactic Center. The catalog includes information on periodicity, binarity, terminal wind velocities, correlations with open clusters, OB associations, H I bubbles, H II regions, and ring nebulae, observed and dereddened narrow-band bv photometry, and distances, both heliocentric and galactocentric, and lists the references from which this information was obtained. This catalog was created by the HEASARC in April 2001, based on electronic versions of Tables 13, 14, 15, and 28 from the published paper containing the catalog which were directly supplied to the HEASARC by the author. This is a service provided by NASA HEASARC .
104. TLUSTY BSTAR2006
- ID:
- ivo://svo.cab/models/tlusty_bstarbin
- Title:
- TLUSTY BSTAR2006
- Short Name:
- TLUSTY BSTAR2006
- Date:
- 04 Sep 2019 08:31:00
- Publisher:
- SVO CAB
- Description:
- TLUSTY BSTAR2006 Grid: Early B-type stars, Teff = 15000K - 30000 K (Lanz, T., Hubeny, I. 2007, ApJS, 169, 83)
105. TLUSTY OSTAR2002
- ID:
- ivo://svo.cab/models/tlusty_ostarbin
- Title:
- TLUSTY OSTAR2002
- Short Name:
- TLUSTY OSTAR2002
- Date:
- 04 Sep 2019 08:31:38
- Publisher:
- SVO CAB
- Description:
- TLUSTY OSTAR2002 Grid: O-type stars, Teff = 27500K - 55000 K (Lanz, T., & Hubeny, I. 2003, ApJS, 146, 417)
- ID:
- ivo://svo.cab/models/tlusty_mergedbin
- Title:
- TLUSTY OSTAR2002+BSTAR2006
- Short Name:
- TLUSTY Merged
- Date:
- 04 Sep 2019 08:31:19
- Publisher:
- SVO CAB
- Description:
- TLUSTY OSTAR2002+BSTAR2006 Grid, The merged files use the BSTAR2006 models for effective temperatures up to 30,000 K and the OSTAR2002 models for higher temperatures.
107. TMAP
- ID:
- ivo://svo.cab/models/tmap
- Title:
- TMAP
- Short Name:
- TMAP
- Date:
- 04 Sep 2019 08:31:00
- Publisher:
- SVO CAB
- Description:
- TMAP. Hydrogen+Helium NLTE Models
108. TMAP (Grid 1)
- ID:
- ivo://svo.cab/models/tmap1
- Title:
- TMAP (Grid 1)
- Short Name:
- TMAP (Grid 1)
- Date:
- 04 Sep 2019 08:31:00
- Publisher:
- SVO CAB
- Description:
- TMAP. Hydrogen+Helium NLTE Models
- ID:
- ivo://nasa.heasarc/tycho2
- Title:
- Tycho-2 Catalog of the 2.5 Million Brightest Stars
- Short Name:
- Tycho-2
- Date:
- 07 Mar 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The Hipparcos and Tycho catalogs are the primary products of the European Space Agency's astrometric mission, Hipparcos. The satellite, which operated for four years, returned high quality scientific data from November 1989 to March 1993. The Tycho-2 catalog is an astrometric reference catalog containing positions and proper motions as well as two-color photometric data for the 2.5 million brightest stars in the sky. The Tycho-2 positions and magnitudes are based on precisely the same observations as the original Tycho catalog (hereafter Tycho-1; see <a href="https://cdsarc.cds.unistra.fr/ftp/cats/I/239">CDS Cat. I/239</a>) collected by the star mapper of the ESA Hipparcos satellite, but Tycho-2 is much bigger and slightly more precise, owing to a more advanced reduction technique. Components of double stars with separations down to 0.8 arcsec are included. Proper motions precise to about 2.5 mas/yr are given as derived from a comparison with the Astrographic Catalogue and 143 other ground-based astrometric catalogs, all reduced to the Hipparcos celestial coordinate system. Tycho-2 supersedes in most applications Tycho-1, as well as the ACT (<a href="https://cdsarc.cds.unistra.fr/ftp/cats/I/246">CDS Cat. I/246</a>) and the TRC (CDS Cat. I/250) catalogs based on Tycho-1. Supplement-1 (not part of this HEASARC database but available at <a href="https://cdsarc.cds.unistra.fr/ftp/cats/I/259/suppl_1.dat.gz">https://cdsarc.cds.unistra.fr/ftp/cats/I/259/suppl_1.dat.gz</a>) lists stars from the Hipparcos and Tycho-1 catalogs which are not in Tycho-2. Supplement-2 (not part of this HEASARC database but available at <a href="https://cdsarc.cds.unistra.fr/ftp/cats/I/259/suppl_2.dat.gz">https://cdsarc.cds.unistra.fr/ftp/cats/I/259/suppl_2.dat.gz</a>) lists 1146 Tycho-1 stars which are probably either false or heavily disturbed. The principal characteristics of the Tycho-2 catalog are summarized below. By means of proper motions the positions are transferred to the year 2000.0, the epoch of the catalog. The median values of internal standard errors are given: <pre> Mean satellite observation epoch ~J1991.5 Epoch of the Tycho-2 catalog J2000.0 Reference system ICRS coincidence with ICRS (1) +/-0.6 mas deviation from inertial (1) +/-0.25 mas/yr Number of entries 2,539,913 Astrometric standard errors (2) V_T < 9 mag 7 mas all stars, positions 60 mas all stars, proper motions 2.5 mas/yr Photometric std. errors (3) on V_T V_T < 9 mag 0.013 mag all stars 0.10 mag Star density b= 0 deg 150 stars/sq.deg. b= +/-30 deg 50 stars/sq.deg. b= +/-90 deg 25 stars/sq.deg. Completeness to 90 per cent V ~ 11.5 mag Completeness to 99 per cent V ~ 11.0 mag Number of Tycho observations ~300 10<sup>6</sup> Note (1): about all 3 axes Note (2): ratio of external to internal standard errors is ~1.0 for positions and for proper motions. Systematic errors are less than 1 mas and 0.5 mas/yr Note (3): ratio of photometric external to internal standard errors at V_T > 9 mag is below 1.5 </pre> For more information on the original catalog, please consult the Tycho-2 home page at <a href="http://www.astro.ku.dk/~erik/Tycho-2">http://www.astro.ku.dk/~erik/Tycho-2</a> For more information on the HEASARC implementation of the Tycho-2 catalog, please consult <a href="#heasarc_implementation">the "HEASARC Implementation" section</a> of this help. This database table was created at the HEASARC in June 2000 based on the ADC/<a href="https://cdsarc.cds.unistra.fr/ftp/cats/I/259">CDS Catalog I/259</a>, using the file tyc2.dat. Galactic coordinates (calculated by converting the observed ICRS Equatorial positions) were added to this HEASARC database table in August 2005. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/ulxrbcat
- Title:
- Ultraluminous X-Ray Sources in External Galaxies Catalog
- Short Name:
- ULXRB
- Date:
- 07 Mar 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table is a catalog of ultraluminous X-ray sources (ULXs) in external galaxies, where ULXs have been defined as compact, off-nuclear X-ray sources with X-ray luminosities in the range of 10<sup>39</sup> - 10<sup>41</sup> erg/s. The aim of this catalog is to provide easy access to the properties of ULXs, their possible counterparts at other wavelengths (optical, IR, and radio), and the properties of their host galaxies. The catalog contains 229 ULXs found in 85 galaxies which had been reported in the astronomy literature as of April 2004. Most ULXs are stellar-mass-black hole X-ray binaries, but it cannot be excluded that some ULXs might be intermediate-mass black holes. A small fraction of the candidate ULXs might be background Active Galactic Nuclei (AGN) or Supernova Remnants (SNRs). ULXs with luminosity above 10<sup>40</sup> erg/s are found in both starburst galaxies and in the halos of early-type galaxies. Some notes on individual galaxies and/or ULXs in this catalog can be found in the file <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/A+A/429/1125/notes.dat">https://cdsarc.cds.unistra.fr/ftp/cats/J/A+A/429/1125/notes.dat</a> which is available at the CDS. This table was created by the HEASARC in January 2005, based on CDS tables J/A+A/429/1125/table1a.dat and table1b.dat. It was updated in September 2012 to correct an error in the declination signs of the NGC 253 objects. This is a service provided by NASA HEASARC .
