SUMMARY OF PROPOSAL 53027
MULLARD SPACE SCIENCE LABORATORY
SURREY UK RH5 6NT
DORKING
HOLMBURY ST. MARY
Tel: +1483 204157 Fax: +1483 278312
Medium: 4GBDAT
Subject: AGN
INVESTIGATING THE STEEP, SOFT POWER-LAW IN THE X-RAY SPECTRUM OF THE EUV-SELECTED AGN, REJ2248-511.
ABSTRACT
The ROSAT PSPC spectrum of the EUV-selected AGN REJ2248-511 (z=0.10) shows an unusual degree of curvature; already soft between 0.3-2keV (with an energy index of 1.6), it steepens further at lower energies to form a `true' ultra-soft X-ray excess. This poses a problem for the nature of the alpha=1.6 power-law; is this the softening of the more typical alpha=1 hard X-ray continuum, or is it an extrapolation of an unusually soft X-ray power-law slope? We request ASCA observations to measure the index of the 1-10keV spectrum; the results will test the nature of the 0.1-2keV X-rays measured by ROSAT and challenge models of what has previously been considered to be the `canonical' X-ray power-law in AGN.
CO-INVESTIGATORS
TARGETS
| TARGET NAME | PRI | RA | DEC | TIME | TC | OFF | GIS | SIS CNT | OBS |
|---|
| 1)REJ2248-511 | 1 | 342.1708 | -51.1650 | 20 ks | N | Y | P | 0.39000 | 1 |