SIMBAD references

2001A&A...367..470G - Astronomy and Astrophysics, volume 367, 470-486 (2001/2-4)

X-ray variability in a complete sample of soft X-ray selected AGN.

GRUPE D., THOMAS H.-C. and BEUERMANN K.

Abstract (from CDS):

We present ROSAT All-Sky Survey and ROSAT pointed observations (PSPC and HRI) of a complete sample of 113 bright soft X-ray AGN selected from the ROSAT Bright Source Catalog. We compare these observations in order to search for extreme cases of flux and spectral X-ray variability - X-ray transient AGN. Three definite transients and one transient candidate are found. The other sources show amplitude variations typically by factors of 2-3 on timescales of years. We found that the variability strength on timescales of days is a function of the steepness of the X-ray spectrum: steeper X-ray objects show stronger variability than flat X-ray spectrum sources. We also present new HRI measurements of our extreme X-ray transients IC 3599 and WPVS 007. We discuss possible models to explain the X-ray transience and the variabilities observed in the non-transient sources.

Abstract Copyright:

Journal keyword(s): accretion, accretion disks - galaxies: active - galaxies: nuclei of - galaxies: Seyfert - quasars: general

CDS comments: misprint 1H 0419+577 instead of 1H 0419-577

Simbad objects: 118

goto Full paper

goto View the reference in ADS

To bookmark this query, right click on this link: simbad:2001A&A...367..470G and select 'bookmark this link' or equivalent in the popup menu


2019.10.20-12:00:25

© Université de Strasbourg/CNRS

    • Contact