Properties Of The Hard X-ray Radiation From The Black Hole Candidates: Cygnus X-1 And 1E1740.7-2942

Details Properties Of The Hard X-ray Radiation From The Black Hole Candidates: Cygnus X-1 And 1E1740.7-2942 Properties Of The Hard X-ray Radiation From The Black Hole Candidates: Cygnus X-1 And 1E1740.7-2942

1997-08-29

arxiv.org/abs/astro-ph/9708270v1

Astronomy and Astrophysics

Astrophysics

6 pages, 7 figures, uses mn.sty, epsf.sty, psfig.tex; Accepted for publication in MNRAS; Also available at http://hea.iki.rs

Scientific paper

The entire dataset of the GRANAT/SIGMA observations of Cyg X-1 and 1E1740.7-2942 in 1990-1994 was analyzed in order to search for correlations between primary observational characteristics of the hard X-ray (40-200 keV) emission - hard X-ray luminosity, hardness of the spectrum (quantified in terms of the best-fit thermal bremsstrahlung temperature kT) and the RMS of short-term flux variations. Although no strict point-to-point correlations were detected certain general tendencies are evident. It was found that for Cyg X-1 the spectral hardness is in general positively correlated with relative amplitude of short-term variability. The correlation of similar kind was found for X-ray transient GRO J0422+32 (X-ray Nova Persei 1992). For both sources an approximate correlation between kT and L_X was found. At low hard X-ray luminosity - below 10E37 erg/sec - kT increases with L_X. At higher luminosity the spectral hardness depends weaker or does not depend at all on the hard X-ray luminosity. The low luminosity end of these approximate correlations (low kT and low RMS) corresponds to extended episodes of very low hard X-ray flux occurred during SIGMA observations.

Affiliated with

Also associated with

No associations

Rating

Properties Of The Hard X-ray Radiation From The Black Hole Candidates: Cygnus X-1 And 1E1740.7-2942 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 Properties Of The Hard X-ray Radiation From The Black Hole Candidates: Cygnus X-1 And 1E1740.7-2942, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Properties Of The Hard X-ray Radiation From The Black Hole Candidates: Cygnus X-1 And 1E1740.7-2942 will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-519537