SUMMARY OF PROPOSAL 61190
ISAS
KANAGAWA JAPAN 229
SAGAMIHARA
3-1-1 YOSHINODAI
Tel: +81-427-3911 EX 2617 Fax: +81-427-59-4253
Medium: 4GBDAT
Subject: CLUSTERS OF GALAXIES AND SUPERCLUSTERS
THE DISTANT RADIO GALAXY WITH A GIANT LUMINOUS ARC; 3C220.1
ABSTRACT
3C220.1 is a radio galaxy located at z=0.62, and revealed to have a "giant luminous arc". Such arcs are known to be images of background galaxies produced by the gravitational lensing effect. The arc radius of 3C220.1(= 9") implies "minimum" velocity dispersion of 720km/sec, which means that the lens potential is provided by a cluster of galaxies rather than a galaxy. Then it's very puzzling that the galaxy population of the fictitious cluster is apprerently very poor. We have analyzed the public archival data of ROSAT HRI to find an extended X-ray emission from the 3C220.1. We propose ASCA observations to determine the temperature and the redshift of the hot gas in the cluster. It will be a strong test to confirm the existence of deep cluster potentical well at z=0.62.
CO-INVESTIGATORS
| CO-I NAME | INSTITUTE | COUNTRY |
|---|
| KAZUHISA MITSUDA | ISAS | JAPAN |
| YASUSHI FUKAZAWA | UNIVERSITY OF TOKYO | JAPAN |
TARGETS
| TARGET NAME | PRI | RA | DEC | TIME | TC | OFF | GIS | SIS CNT | OBS |
|---|
| 1)3C220.1 | 2 | 143.1654 | 79.1088 | 40 ks | N | Y | P | 0.02800 | 1 |