SUMMARY OF PROPOSAL 62159
NASA GODDARD SPACE FLIGHT CENTER
GREENBELT
MD USA 20771
Tel: 301-286-7579 Fax: 301-286-1684
Medium: 4GBDAT
Subject: CLUSTERS OF GALAXIES AND SUPERCLUSTERS
ASCA OBSERVATIONS OF ROSAT ALL-SKY SURVEY SELECTED GROUPS
ABSTRACT
Although ROSAT pointed observations have shown that many groups emit X-rays, the groups with the highest ROSAT flux are expected to be found in the All Sky Survey (RASS). Here, we propose continued observation of the brightest X-ray selected groups from a cross-correlation of the RASS with an optical catalog of groups from the Zwicky catalog. There are now only ~ dozen ASCA spectra for groups, and these show that groups vary widely in their abundance and baryon fraction. Continued high quality spectral measurements will help us understand this variation: the data will provide temperature and abundance profiles as well as the abundance of Si relative to Fe to constrain the origin of the X-ray emitting gas, the form of the potential, and the total mass of these systems.
CO-INVESTIGATORS
| CO-I NAME | INSTITUTE | COUNTRY |
|---|
| UNA HWANG | NASA GSFC | USA |
| RICHARD WHITE | NASA GSFC | USA |
| JACK BURNS | NEW MEXICO STATE U. | USA |
| MICHAEL LEDLOW | NEW MEXICO STATE U. | USA |
TARGETS
| TARGET NAME | PRI | RA | DEC | TIME | TC | OFF | GIS | SIS CNT | OBS |
|---|
| 1)S49-140 | 2 | 29.0958 | 5.6269 | 40 ks | N | N | P | 0.09000 | 1 |
| 2)S34-175 | 1 | 258.8392 | 57.3786 | 25 ks | N | N | P | 0.22000 | 1 |
TARGET 1
MUST CHOOSE CORRECT PAIR OF CCD CHIPS, DEPENDING ON DATE OF OBSERVATION
TARGET 2
MUST CHOOSE CORRECT PAIR OF CCD CHIPS, DEPENDING ON DATE OF OBSERVATION