IXO Populations in Starburst and Low-Luminosity AGN Galaxies
Abstract
A Chandra guaranteed-time program is surveying an H-alpha selected sample of galaxies, most of which are known to harbor a low-luminosity AGN or starburst. I will report on the detection rate of IXOs in these galaxies and their X-ray color properties. Preliminary results suggest that the detection rate is ~ 0-1 IXO per galaxy, with more active galaxies tending to have more candidates. Similarly, a survey of HRI data from nearby galaxies also suggests that starburst galaxies tend to have an enhanced number of IXOs. One possibility is that ``top-heavy'' IMFs in starburst galaxies result in progenitor stars sufficiently massive to produce black holes exceeding 10Msun more often than is the case with normal (e.g., solar-neighborhood) IMFs. The best-studied starburst galaxy with a large number of IXOs is NGC 253, and a detailed analysis of the temporal and spectral properties of its IXOs derived from Chandra, XMM-Newton, ASCA and ROSAT data will be discussed.
- Publication:
-
American Astronomical Society Meeting Abstracts #198
- Pub Date:
- May 2001
- Bibcode:
- 2001AAS...198.5007P