Previous abstract Next abstract

Session 62 - X-ray Astronomy: New Discoveries.
Oral session, Tuesday, January 16
1st Floor, La Villita Assembly Building

[62.03] X-ray Emission from Clusters of Galaxies - A Cosmological Laboratory

R. Mushotzky (NASA/GSFC)

In the last 5 years our knowledge of the x-ray emission from clusters has exploded with high quality Rosat image and ASCA spectra. We are now able to obtain detailed measurements of the mass and mass distribution of clusters out to radii of \ 2 Mpc for relaxed systems.over a a mass range from 10^13-4^15 solar masses. In addtion the abundances of O, Si, S, and Fe can be reliably obtained over the same mass range. For massive clusters the elemental ratios strongly indicate that type II supernova were responsible for most of the metals. However less massive systems may have a substantial contribution from type Is, The total mass of alpha burning elements strongly indicates that most galaxies went through a extremely luminous early phase which resulted in the ejetion of \ 1/2 of their total mass. The Fe abundance as a function of redshift shows little if any change out to redshifts of \ 0.5 confirming the early enrichment of the intergalactic medium in clusters. Detailed temperature maps for merging systems have shown direct evidence for interaction and allow modeling of these complex systems.

Program listing for Tuesday