Effect of Coulomb Collisions on the Sunyaev-Zel'dovich Effect of Galaxy Clusters
Abstract
Sunyaev-Zel'dovich effect (SZE) is a new observational probe that promises to provide new insights into cosmology and plasma astrophysics of galaxy clusters. The SZE is a distortion in the cosmic microwave background spectrum caused by hot electrons produced by shock-heating of intergalactic medium in the cluster outskirts. During the shock-heating, most of the kinetic energy goes into ions and little to electrons. Electrons and ions eventually equilibrate through Coulomb collisions. But, the equilibration time is longer than the age of the Universe for the low-density plasma. This causes the electron temperature to be considerably smaller than the ion temperature in cluster outskirts. In this work, we investigate the electron-ion equilibration process in galaxy clusters and their implications for upcoming SZE cluster surveys.
- Publication:
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American Astronomical Society Meeting Abstracts #214
- Pub Date:
- May 2009
- Bibcode:
- 2009AAS...21430705P