ULXRB ivo://nasa.heasarc/ulxrbcat NASA/GSFC HEASARC Liu, Mirabel 2026-04-03 NASA/GSFC HEASARC help desk heasarc-vo at athena.gsfc.nasa.gov Star XRB 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 . 2005A&A...429.1125L https://heasarc.gsfc.nasa.gov/W3Browse/all/ulxrbcat.html Catalog Research served-by HEASARC TAP https://heasarc.gsfc.nasa.gov/xamin/vo/cone?showoffsets&table=ulxrbcat& GET text/xml 180 99999 true 49.59308333 -66.60102222 0.0166666666666667 https://heasarc.gsfc.nasa.gov/xamin/vo/tap https://heasarc.gsfc.nasa.gov/cgi-bin/W3Browse/getvotable.pl?name=ulxrbcat GET text/xml https://heasarc.gsfc.nasa.gov/cgi-bin/W3Browse/w3query.pl?tablehead=name=heasarc_ulxrbcat&Action=More+Options&Action=Parameter+Search&ConeAdd=1 STAR CATALOG 0.0166666666666667 X-ray public ulxrbcat Ultraluminous X-Ray Sources in External Galaxies Catalog dec Declination degree pos.eq.dec;meta.main double nullable morph_type Morphological Type of Host Galaxy from RC3 src.morph.type double nullable name Ultraluminous X-Ray (ULX) Source Designation meta.id;meta.main char nullable ks_mag_gal K_s Magnitude of Host Galaxy mag phot.mag;em.IR.K double nullable morph_type_2 Morphological Type of Second Galaxy When Pair src.morph.type double nullable ra Right Ascension degree pos.eq.ra;meta.main double nullable "__row" System index column char nullable "distance" Distance to Host Galaxy (Mpc) Mpc pos.distance double nullable alt_galaxy_name Alternative Host Galaxy Designation meta.id char nullable lower_energy Lower Limit of Energy Range (keV) keV em.energy double nullable bmag_gal_2 B Magnitude of Second Galaxy When Pair mag phot.mag;em.opt.B double nullable galaxy_name Host Galaxy Designation meta.id char nullable nuclear_offset Nuclear Offset (arcsec) arcsec pos.angDistance double nullable fir_mag_gal Far Infrared Magnitude of Host Galaxy mag phot.mag;em.IR double nullable bii Galactic Latitude degree pos.galactic.lat double nullable nh_gal Galactic Hydrogen Column Density from Dickey & Lockman (H-atoms/cm^2) H-atoms/cm^2 phys.columnDensity double nullable nh_gal_2 Higher Galactic Hydrogen Column Density When Interval (H-atoms/cm^2) H-atoms/cm^2 phys.columnDensity double nullable upper_energy Upper Limit of Energy Range (keV) keV em.energy double nullable model_params Spectral Index for Power-Law Fit, Inner Temperature (keV) for Thermal Model Fit meta.code;spect;meta.modelled char nullable bmag_gal B-Band Photographic Magnitude of Host Galaxy from RC3 mag phot.mag;em.opt.B double nullable "__x_ra_dec" System unit vector column double nullable model_type Best-Fit Model of Recent X-Ray Observation of ULX meta.note char nullable hubble_class Hubble Classification Type of Host Galaxy from RC3 src.morph.type char nullable "__z_ra_dec" System unit vector column double nullable ks_mag_gal_2 K_s Magnitude of Second Galaxy When Pair mag phot.mag;em.IR.K double nullable alt_name Other Designation of the ULX Source meta.id char nullable lii Galactic Longitude degree pos.galactic.lon double nullable "__y_ra_dec" System unit vector column double nullable lx X-Ray Luminosity (erg/s) erg/s phys.luminosity;em.X-ray double nullable