M 33 XMM-Newton X-Ray Variability Source Catalog

Together with the hardness ratio method and cross-correlation with optical, infrared, and radio data, the authors also classified or confirmed previous classification of 25 supernova remnants and candidates, 2 X-ray binaries, and 11 super-soft source candidates (7 of which are new SSS candidates). In addition, they classified 13 active galactic nuclei and background galaxies, 6 stars, and 23 foreground star candidates in the direction of M 33.

A further 206 objects are classified as 'hard', approximately half of which are sources intrinsic to M 33. The relative contribution of the classified XRB and SSS in M 33 is now comparable to M 31. The luminosity distribution of SNRs in both spiral galaxies is almost the same, although the number of the detected SNRs in M 33 remains much higher.

This table was created by the HEASARC in March 2007 based on the CDS table J/A+A/448/1247 file table4.dat. The CDS has another table which lists the properties of the sources detected on an observation-by-observation basis which is not included as part of this Browse table but is available at <a href="cdsarc.cds.unistra.fr/ftp/cats/J/A+A/448/1247/table5.dat.gz">https://cdsarc.cds.unistra.fr/ftp/cats/J/A+A/448/1247/table5.dat.gz</a> This is a service provided by NASA HEASARC .