04/23/02
KAWAGUCHI Toshihiro Observatoire Paris-Meudon
5, Place Jules Janssen PCHE-
92195 Meudon, France
Presentation 1 : Oral
X-ray Spectrum of Super-Eddington Accretion Disk and Age of Supermassive Black Holes
Toshihiro KAWAGUCHI
Effects of electron scattering (opacity and Comptonization) on the emergent X-ray spectrum from super-Eddington accretion flows (the so called slim disks) are examined. The model is applied to Narrow-Line Seyfert 1 galaxies (NLS1s) to estimate their accretion rates. We found that a NLS1, PG 1448+273, has an extremely large accretion rate: about 1000 L_Edd / c^2. This implys that this object is really young: its inferred age (black-hole mass divided by the accretion rate) is 10^6 years.