Origin of the Hard X-ray Emission in Star-Forming Galaxies
Abstract
X-ray analysis of Lyman alpha- and X-ray-emitting star-forming galaxies has revealed the presence of both soft and hard X-ray emissions. Star formation activity releases into the medium large amounts of mechanical energy through stellar winds and supernova explosions. These winds interact and heat the gas surrounding the stellar clusters producing the observed diffuse, soft X-ray emission (0.1-2.0~keV) with a typical temperature of kT~0.3-0.7~keV. In addition to this diffuse, soft component, a harder X-ray component (2.0-10.0~keV) is found in this type of galaxies, with an intensity of the order of the soft emission. A composite of massive X-ray binaries could account for this component, as expected from the evolution of a starburst having formed stars during some millions of years. In some cases the presence of Ultra-luminous X-ray Sources is required to explain the conspicuous hard X-ray emission observed. The presence of a number of ultra-compact sources in binary systems emitting hard X-rays could mimic the properties of low-luminosity AGN. In this talk we will discuss the observations of a number of such star-forming galaxies and the implications on the starburst-AGN connection.
- Publication:
-
The Starburst-AGN Connection under the Multiwavelength Limelight
- Pub Date:
- November 2011
- Bibcode:
- 2011sacm.confE...8O