[Previous] | [Session 7] | [Next]
S.P. Oh, M. Matuszewski, R.D. Blandford (Caltech)
Cosmic rays are generated in clusters both at intergalactic and accretion shocks and by direction injection from sources such as radio galaxies. Since the cosmic rays evolve adiabatically, as the gas cools, non-thermal pressure support eventually becomes dominant. This allows the gas to resist runaway compression and cooling. In particular, the X-ray emission is reduced since the compressive work done on the cooling gas (which must subsequently be radiated away) is reduced. We investigate whether this transition to near isochoric cooling at high gas densities and low temperatures can account for the greatly reduced emission measure of spectral cooling lines below 2 keV observed by Chandra and XMM in several cooling flow clusters.