SUMMARY OF PROPOSAL 43045
DR. HAIDA LIANG
CEA
 FRANCE 91191
GIF-SUR-YVETTE
ORME DES MERISIERS

  E-mail: HLIANG@ARIANE.SACLAY.CEA.FR	Tel: 33-1-6908-3492	Fax: 33-1-6908-6577
  Medium: 2GBDAT

Subject: CLUSTERS OF GALAXIES AND SUPERCLUSTERS                      
  Title: A MEASUREMENT OF THE GAS TEMPERATURE OF THE NEARBY LENSING CLUSTER A2104        


Abstract:
 We intend to study one of the lowest redshift clusters with gravitational lensing
 arcs to test the validity of the assumption of hydrostatic equilibrium by combining
 a lensing analysis of the cluster potential with that of the X-ray data. The low
 redshift of this cluster allows us to probe closer into the core of the cluster than
 other lensing clusters. We have obtained 90 galaxy spectra with the CFHT and deep
 images with the NTT. We have also been allocated 50ksec of ROSAT HRI time. A
 combined study of the cluster mass distribution using constraints from lensing,
 X-ray and galaxy velocity dispersion data will allow us to further clarify the
 inconsistencies currently found between the different methods of mass estimates. The cluster temperature is central to this debate.

 Co-Is:
   1  MARGUERITE PIERRE   	CEA                           FRANCE    
      (No Co-I contact data)
   2  TAKESHI TSURU       	UNIVERSITY OF KYOTO           JAPAN     


Target Name           PRI RA        Dec        Time TC  Off GIS SIS_Cts  Obs
-------------------   --- --------  --------   ---- --  --- --- -------  ---
A2104                  1  235.0283   -3.2942    50   N   Y   P  0.50460   1