Implications of the Observed Ultra-luminous X-ray Source Luminosity Function
Abstract
We present the X-ray luminosity function and other properties of a complete sample of 127 nearby galaxies containing 107 ultraluminous X-ray (ULX) sources with 0.3-10.0 keV luminosities in excess of 1e39 erg/s. The luminosity function shows a break or cut-off at high luminosities that deviates from its pure power-law distribution at lower luminosities. The cut-off is at roughly the Eddington luminosity for a 70-150 solar mass accretor. We examine the effects on the observed luminosity function of sample biases, of small-number statistics (at the high luminosity end), and of measurement uncertainties. We consider the physical implications of the shape and normalization of the observed luminosity function. The sample selection criteria and the basic properties of the sample galaxies are also presented and the luminosity function is also compared and contrasted to results of other recent surveys.
- Publication:
-
American Astronomical Society Meeting Abstracts #219
- Pub Date:
- January 2012
- Bibcode:
- 2012AAS...21924708S