XMM-Newton observation of the X-ray point source population of the starburst galaxy IC 342
Abstract
We present the results of an XMM-Newton observation of the starburst galaxy IC 342. Thirty-seven X-ray point sources were detected down to a luminosity limit of ~1037 erg s-1. Most of the sources are located near the spiral arms. The X-ray point source luminosity function is consistent with a power-law shape with a slope of 0.55, typical of starburst galaxies. We also present the energy spectra of several ultraluminous X-ray sources (ULXs), including the luminous X-ray source in the galactic nucleus. Except for the nucleus and a luminous supersoft X-ray source, other ULXs can generally be fitted with a simple power-law spectral model. The nucleus is very luminous (~1040 erg s-1 in 0.2-12 keV) and requires disc blackbody and power-law components to describe the X-ray emission. The spectral fit reveals a cool accretion disc (kT= 0.11 keV) and suggests that the source harbours either an intermediate-mass black hole or a stellar-mass black hole with outflow.
- Publication:
-
Monthly Notices of the Royal Astronomical Society
- Pub Date:
- November 2003
- DOI:
- 10.1046/j.1365-2966.2003.07086.x
- arXiv:
- arXiv:astro-ph/0308106
- Bibcode:
- 2003MNRAS.346..265K
- Keywords:
-
- galaxies: individual: IC 342;
- galaxies: starburst;
- X-rays: binaries;
- X-rays: galaxies;
- Astrophysics
- E-Print:
- 8 pages, 7 figures, accepted for publication in MNRAS