SUMMARY OF PROPOSAL 41230
PROF YASUO TANAKA
ISAS
KANAGAWA JAPAN 229
SAGAMIHARA
3-1-1 YSHINODAI

  E-mail: TANAKA@ASTRO.ISAS.AC.JP	Tel: 49 89 3299 3881	Fax: 49 89 3299 3569
  Medium: 4GBDAT

Subject: CLUSTERS OF GALAXIES AND SUPERCLUSTERS                      
  Title: A STUDY OF FOUR DISTANT, EXTREMELY X-RAY LUMINOUS GALAXY CLUSTERS               


Abstract:
 Distant clusters of galaxies are important cosmological probes. The rapid evolution
 of clusters as observed in the evolution of the X-ray luminosity function provides
 strong contraints on cosmological models. The most massive, X-ray luminous clusters
 are the most important objects in this respect. We therefore propose to observe four
 extremely X-ray luminous galaxy clusters detected in the ROSAT All Sky Survey. We
 like to determine their gas temperatures and iron abundances for comparison of these
 properties with those of nearby clusters. In connection with scheduled ROSAT HRI
 observations we like to determine the cluster masses and gas mass fractions. These
 objects will also be important targets for gravitational lensing and Sunyaev-Zel'dovich effect studies.

 Co-Is:
   1  TAKAYA OHASHI       	TOKYO METROP. UNIV.           JAPAN     
      (No Co-I contact data)
   2  MAKOTO HATTORI      	MPE                           GERMANY   
   3  SABINE SCHINDLER    	MPE                           GERMANY   
   4  WOLFGANG VOGES      	MPE                           GERMANY   
   5  HANS BOEHRINGER     	MPE                           GERMANY   


Target Name           PRI RA        Dec        Time TC  Off GIS SIS_Cts  Obs
-------------------   --- --------  --------   ---- --  --- --- -------  ---
RXJ0949+1708           2  147.4792   17.1344    40   N   Y   P  0.20000   1 
          
RXJ0658-5557           2  104.6375  -55.9553    40   N   Y   P  0.20000   1