Supernova rates in Abell galaxy clusters and implications for metallicity

Abstract

Supernovae (SNe) play a critical role in the metal enrichment of the intra-cluster medium (ICM) in galaxy clusters. Not only are SNe the main source for metals, but they may also supply the energy to eject enriched gas from galaxies by winds. However, measurements of SN rates in galaxy clusters have not been published to date. We have initiated a program to find SNe in 163 medium-redshift (0.06<z<0.2) Abell clusters, using the Wise Observatory 1m telescope. Our program has already discovered 11 spectroscopically confirmed SNe at z=0.1 - 0.24, and several unconfirmed SNe. We present the main scientific goals of this project, and discuss a novel explanation for the centrally enhanced metal abundances indicated by X-ray observations of galaxy clusters, based on the contribution of intergalactic SNe.

2 pages, latex, include conf-X.sty, one figure, to appear in the proceedings of the workshop "Large Scale Structure in the X-ray Universe", held in Santorini, Greece, September 1999, eds. M. Plionis and I. Georgantopoulos (Editions Frontieres)