SUMMARY OF PROPOSAL 41268 MR. HIRONORI MATSUMOTO KYOTO UNIVERSITY KYOTO JAPAN 606-01 KYOTO KITASHIRAKAWA OIWAKECHOU, SAKYO-KU E-mail: MATUMOTO@CR.SCPHYS.KYOTO-U.AC.JP Tel: 075-753-3869 Fax: 075-701-5377 Medium: 2.5GB8MM Subject: CLUSTERS OF GALAXIES AND SUPERCLUSTERS Title: X-RAY STUDY OF PRIMORDIAL GAS IN "PRIMATURE" CLUSTER OF GALAXIES Abstract: It has been reported that primordial gas was dound in A548 with ROSAT observation. We will have the first chance to observe primordial gas directly, if this report is true. So we propose the observation of A548. Co-Is: 1 TAKESHI TSURU KYOTO UNIV. JAPAN (No Co-I contact data) 2 HIROSHI TOMIDA KYOTO UNIV. JAPAN 3 YUTAKA FUJITA KYOTO UNIV. JAPAN Target Name PRI RA Dec Time TC Off GIS SIS_Cts Obs ------------------- --- -------- -------- ---- -- --- --- ------- --- A548-1 2 86.7500 -25.1667 70 N Y P 0.04500 1 A548-2 2 87.1667 -25.4750 30 N Y P 0.23000 1