An Inverse Compton Process for the Excess Diffuse EUV Emission from the Virgo and Coma Galaxy Clusters
Chorng-Yuan Hwang
The excess extreme-ultraviolet (EUV) emission detected in
the Virgo and Coma clusters is explained by inverse Compton scattering of cosmic microwave background photons, which are scattered by the
relativistic electrons that account for the extended radio synchrotron
emission of these clusters. The lower limits of the average magnetic
fields of these clusters estimated from the EUV excess are close to the
equipartition magnetic fields derived from radio observations,
indicating that the electron energies and magnetic field energies might
be close to equipartition. The excess emission suggests energy
reservoirs of ~1061 and ~1060 ergs for the
Coma and Virgo clusters, respectively.
Institute of Astronomy and Astrophysics, Academia Sinica, Post
Office Box 1-87, Nankang, Taipei, Taiwan 115, Republic of China.