SUMMARY OF PROPOSAL 42190
DR. MEGAN ELIZABETH DONAHUE
SPACE TELESCOPE SCIENCE INSTITUTE
MD USA 21218
BALTIMORE
3700 SAN MARTIN DRIVE

  E-mail: DONAHUE@STSCI.EDU	Tel: 410 338 4701	Fax: 410 338 4717
  Medium: 2GB8MM

Subject: CLUSTERS OF GALAXIES AND SUPERCLUSTERS                      
  Title: AN X-RAY LUMINOUS, DISTANT (Z                                                   


Abstract:
 We propose to complete our program to measure the X-ray temperatures and iron
 abundances of the most distant, X-ray luminous clusters of galaxies known. The final
 cluster in our sample, MS1137+66 (z=0.78), is optically poorer than the other 3, and
 therefore probes a sparser galactic environment. We have observed clusters at z=0.55
 and 0.83 and find high Tx, consistent with Lx, but a low gas-to-total mass ratio
 (6%). The high redshift provides a long lever arm to test models for the evolution
 of the ICM and cluster formation. The cluster is bright and compact enough for ASCA
 spectra; the redshift moves the interesting part of the spectra to ~4 keV. It is
 chosen from a well-defined X-ray selected cluster sample. We have supplementary data from ROSAT, HST, CFHT and soon, Keck.

 Co-Is:
   1  JOHN STOCKE         	UNIV. OF COLORADO             USA       
      (No Co-I contact data)
   2  ISABELLA GIOIA      	IFA, HAWAII                   USA       
   3  GERRY LUPPINO       	IFA, HAWAII                   USA       


Target Name           PRI RA        Dec        Time TC  Off GIS SIS_Cts  Obs
-------------------   --- --------  --------   ---- --  --- --- -------  ---
MS1137.5+6625          0  175.0992   66.1386    78   N   N   P  0.00900   1