High Energy X-Ray Emission in Clusters of Galaxies

Abstract

Observations with the RXTE and SAX satellites have recently led to the measurement of a second component in the spectra of several clusters of galaxies which are known to have regions of extended radio emission. This new component is quite likely nonthermal emission resulting from Compton scattering of relativistic electrons by the cosmic microwave background. The nonthermal X-ray and radio measurements yield the values of the mean intracluster magnetic field, and relativistic electron density, for the first time in extragalactic environments. These results have important consequences on issues such as the origin of cosmic ray electrons and protons, their propagation modes in clusters, and the effects of these particles and magnetic fields on the intracluster gas. The observational results are reviewed, and some of their direct implications are discussed, along with near-future prospects for improved spectral and spatial measurements of nonthermal emission in clusters.

Invited review, proceedings of the Heidelberg Workshop `High Energy Gamma-Ray Astronomy', 9 pages, 2 figures

Cited by in corpus (5)

• Galaxy Clusters in the Swift/BAT era: Hard X-rays in the ICM
• Quantification of Uncertainty in the Measurement of Magnetic Fields in Clusters of Galaxies
• Heating of the Hot Intergalactic Medium by Powerful Radio Galaxies and Associated High Energy Gamma-Ray Emission
• The impact of relativistic corrections and component separation in the measurement of the SZ effect and on the small angular scale non-Gaussianity of the CMB
• Non-thermal X-ray Emission: An Alternative to Cluster Cooling Flows?