SUMMARY OF PROPOSAL 71164
ISAS
3-1-1 YOSHINODAI
SAGAMIHARA
KANAGAWA JAPAN 229-8510
Tel: +81-427-59-8134 Fax: +81-427-59-8455
Medium: 4GBDAT
Subject: CLUSTERS OF GALAXIES AND SUPERCLUSTERS
HIGH-Z CLUSTER 3C324 AND CONSTRAINTS ON THE DENSITY PARAMETER, OMEGA_0
ABSTRACT
The redshift distribution of the population of rich galaxy clusters depends sensitively on the cosmological density parameter, Omega_0. CDM numerical simulations show that the number density of rich, hot clusters at z~1 in an Omega_0=1 universe must be smaller by two orders of magnitude than that in an Omega_0=0.3 universe. Thus if a high temperature, high-z cluster is detected, we obtain a strong constraint on Omega_0; an Omega_0=1 universe can be rule out. We propose ASCA observations of high-z cluster 3C324 (z=1.206), which is thought to be rich and hot from the gravitational-lensing and ROSAT X-ray observations. With 100ksec observations, we can obtain a meaningful lower limit of the temperature which can constrain the density parameter.
CO-INVESTIGATORS
| CO-I NAME | INSTITUTE | COUNTRY |
|---|
| KAZUHISA MITSUDA | ISAS | JAPAN |
| MAKOTO HATTORI | UNIVERSITY OF TOHOKU | JAPAN |
| TATEHIRO MIHARA | RIKEN | JAPAN |
TARGETS
| TARGET NAME | PRI | RA | DEC | TIME | TC | OFF | GIS | SIS CNT | OBS |
|---|
| 1)3C324 | B | 237.4538 | 21.4272 | 100 ks | N | Y | P | 0.00200 | 1 |