Publication Date:
2019-07-13
Description:
ROSAT observations of narrow-line Seyfert 1 galaxies find a very steep soft spectrum and rapid variability. It has been suggested that these properties result from an extreme value of a yet unknown physical parameter; a high accretion rate, low black hole mass or face-on orientation have been suggested. During a Ginga observation of bright NLS1 PKS 0558-504, a flare was observed with rise time so rapid for this luminous object that the emission must be beamed. If reconfirmed, this behavior would support, the face-oil orientation model. PKS 0558-504 is one of the few NLS1s known to be bright enough above 10 keV that good spectral constraints on the reflection component, common in broad-line Seyfert 1s, is possible. A 60ks RXTE observation was performed; however, we failed to detect any large amplitude flares.
Keywords:
Astronomy
Type:
CAL-3122
Format:
text
