Noise Variability in the CYGNUS-X-1 and HERCULES-X-1
Abstract
The aperiodic variability in the X-ray emission of Cyg X-1 and Her X-1 is examined from EXOSAT archive data by means of the production of broad band power spectra. The power spectra of Cyg X-1 show a high rms, a complex shape and variations of the break frequency over one order of magnitude. Good agreement is obtained with a shot noise model with a distribution in shot lifetimes. The noise in Her X-1 shows variations correlated with the 35rd cycle of the source. The observations are consistent with occultation by the inner accretion disk.
- Publication:
-
Two Topics in X-Ray Astronomy, Volume 1: X Ray Binaries. Volume 2: AGN and the X Ray Background
- Pub Date:
- November 1989
- Bibcode:
- 1989ESASP.296..283B
- Keywords:
-
- Cygnus Constellation;
- Noise Spectra;
- Power Spectra;
- Shot Noise;
- Variability;
- X Ray Binaries;
- Emission Spectra;
- Exosat Satellite;
- Frequency Measurement;
- Stellar Radiation;
- Astronomy