Other
Scientific paper
Oct 2000
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2000head....5.3115z&link_type=abstract
American Astronomical Society, HEAD Meeting #5, #31.15; Bulletin of the American Astronomical Society, Vol. 32, p.1234
Other
Scientific paper
We study Cyg X-1 observations by the RXTE/ASM, RXTE/PCA, and CGRO/BATSE. We find that correlations seen in the data between X-ray intensity and hardness ratios can be interpreted in terms of simple physical models. In the hard/low state, the main driver of the variability appears to be a variable flux of soft seed photons cooling a hot thermal plasma. An increase of the soft flux increases the measured X-ray flux but, at the same time, it reduces the plasma temperature, which, in turn, softens the X-ray spectrum, explaining the observed negative correlation between the X-ray hardness and the X-ray flux. We discuss possible accretion scenarios fitting this variability pattern. On the other hand, the X-ray spectrum in the soft/high state consists of a disk blackbody and a high-energy tail. We model the observed spectral variability by variable non-thermal power supplied to flares above an optically-thick, stable, accretion disk. An increase of the non-thermal power results in an increase of the tail amplitude without changing its shape, which explains then the observed positive correlation between the X-ray hardness and the X-ray flux.
Wen Linqing
Zdziarski Andrzej A.
No associations
LandOfFree
The primary drivers of spectral variability in Cyg X-1 does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with The primary drivers of spectral variability in Cyg X-1, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The primary drivers of spectral variability in Cyg X-1 will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-872135