## SUMMARY OF PROPOSAL 51243

#### DR. KOUJUN YAMASHITA YAMASITA@SATIO.PHYS.NAGOYA-U.AC.JP

NAGOYA UNIVERSITY
AICHI-KEN JAPAN 464-01
NAGOYA
FURO-CHO, CHIKUSA-KU
Tel: 81-52-789-3540 Fax: 81-52-789-2919
Medium: 2.5GB8MM
Subject: CLUSTERS OF GALAXIES AND SUPERCLUSTERS

#### ABSTRACT

The measurement of velocity dispersion and plasma temperature indicates that galaxies and intracluster medium(ICM) in an cluster are bound in the same potential. However there are no significant correlations between physical parameters derived from optical and X-ray observations. The detailed optical observations of Abell clusters(z<0.1) in southern sky are carried out by ESO key programme. We have selected two rich clusters, A3128(z=0.0600) and A3695(z=0.0893). We make clear the correlation among the distribution of galaxies, ICM and dark matter in these clusters by combining ASCA data and ESO optical data. This method is aimed at investigating the $\beta$-problem, origin of ICM and cluster merging.