SUMMARY OF PROPOSAL 63034
LANDESSTERNWARTE HEIDELBERG
KOENIGSTUHL
HEIDELBERG
GERMANY 69117
Tel: 49 6221 509237 Fax: 49 6221 509202
Medium: CD ROM
Subject: AGN
THE VARIABLE ABSORBER IN THE HIGH-Z QUASAR S5 0836+710
ABSTRACT
Short term variation of the absorbing column density in the highly redshifted quasar S5 0836+710 (z = 2.172) was previously observed. An increase by a factor 4 within 0.8 years (quasar frame) was reported and sets stringent constraints on the location of the absorber. This is the first finding of relatively high AND variable absorption in a quasar at high redshift and strengthens the hypotheses of a population of absorbed AGN at high redshift which is postulated to explain the X-ray background. To confirm the presence of high and variable absorption and to investigate the time scale of the variation four observations of the quasar S5 0836+710 with ASCA for a total of 80 ksec are proposed.
CO-INVESTIGATORS
| CO-I NAME | INSTITUTE | COUNTRY |
|---|
| | | |
TARGETS
| TARGET NAME | PRI | RA | DEC | TIME | TC | OFF | GIS | SIS CNT | OBS |
|---|
| 1)S5 0836+710 | 3 | 130.3517 | 70.8951 | 80 ks | N | Y | P | 0.30000 | 4 |
TARGET 1
THE OBSERVATION IS NOT MARKED TO BE A MONITORING PROGRAM SINCE THE SPACING OF THE FOUR OBSERVATIONS COULD BE ARRANGED TO FIT THE ASCA SCHEDULE.