Implications of a Nonthermal Origin of the Excess EUV Emission from the Coma Cluster of Galaxies

Astronomy and Astrophysics – Astrophysics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

LaTeX, 6 figures; accepted for publication in ApJ

Scientific paper

10.1086/308828

The inverse Compton (IC) interpretation of the excess EUV emission, that was recently reported from several clusters of galaxies, suggests that the amount of relativistic electrons in the intracluster medium is highly significant, W_e>10^{61} erg. Considering Coma as the prototype galaxy cluster of nonthermal radiation, we discuss implications of the inverse Compton origin of the excess EUV fluxes in the case of low intracluster magnetic fields of order 0.1 muG, as required for the IC interpretation of the observed excess hard X-ray flux, and in the case of high fields of order 1 muG as suggested by Faraday rotation measurements. Although for such high intracluster fields the excess hard X-rays will require an explanation other than by the IC effect, we show that the excess EUV flux can be explained by the IC emission of a `relic' population of electrons driven into the incipient intracluster medium at the epoch of starburst activity by galactic winds, and later on reenergized by adiabatic compression and/or large-scale shocks transmitted through the cluster as the consequence of more recent merger events. For high magnetic fields B > 1 muG the interpretation of the radio fluxes of Coma requires a second population of electrons injected recently. They can be explained as secondaries produced by a population of relativistic protons. We calculate the fluxes of gamma-rays to be expected in both the low and high magnetic field scenarios, and discuss possibilities to distinguish between these two principal options by future gamma-ray observations.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Implications of a Nonthermal Origin of the Excess EUV Emission from the Coma Cluster of Galaxies does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Implications of a Nonthermal Origin of the Excess EUV Emission from the Coma Cluster of Galaxies, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Implications of a Nonthermal Origin of the Excess EUV Emission from the Coma Cluster of Galaxies will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-312082

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.