CIR X-1 : X-ray observations with SAS 3.
Abstract
Eight observations of Cir X-1 with SAS 3, each lasting 1-6 days, have yielded a variety of new phenomena, viz., a luminous state of steady emission, rapid large-intensity dips, an extremely rapid X-ray transition, and bright flares. Through searches for periodic X-ray pulsations were carried out on data trains of duration up to 6 days; upper limits for pulsations with periods greater than 250 microsec range down to 0.3%. Aperiodic variability with characteristic times of 0.4-1.0 sec was observed but is not well characterized by a simple shot noise model. No millisecond bursts were observed during 40,000 sec in three separate observations. Spectral parameters derived before and after several X-ray transitions indicate that the transitions are not due to absorption of X-rays by intervening gas. Models previously proposed for the Cir X-1 system do not easily provide explanations for all the complex phenomena reported herein.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- October 1982
- DOI:
- 10.1086/160334
- Bibcode:
- 1982ApJ...261..228D
- Keywords:
-
- Binary Stars;
- Stellar Models;
- X Ray Sources;
- Autocorrelation;
- Background Radiation;
- Radio Bursts;
- Sas-3;
- Shot Noise;
- Stellar Flares;
- Stellar Luminosity;
- X Ray Spectra;
- Astronomy