ANS results on X-ray binaries.
Abstract
A short description is given of the Astronomical Netherlands Satellite (ANS) and the X-ray instruments of the Space Research Laboratory in Utrecht. The ANS observed in February 1975 a soft (1/4 keV) X-ray flux in Her X-1 during the 'off'-state with an intensity of a factor 10 lower than observed in the 'on'-state. The ANS observations on Cyg X-1 are summarized. During the May 1975 flaring state a very high intensity at 0.5 keV is measured consistent with a power-law photon-spectrum with index 3.5 and an interstellar absorption of 7.10 to the 21st power atoms/sq cm, but not consistent with spectra that show an additional cut-off below 1 KeV and an absorption of 7.10 to the 21st power atoms/sq cm. Intensity changes on a time scale of minutes, as observed in Cyg X-1 low state, are not observed during the flaring state.
- Publication:
-
NASA Special Publication
- Pub Date:
- 1976
- Bibcode:
- 1976NASSP.389...27H
- Keywords:
-
- Astronomical Netherlands Satellite;
- Binary Stars;
- X Ray Binaries;
- X Ray Sources;
- Absorption Spectra;
- Interstellar Radiation;
- Power Spectra;
- Satellite Observation;
- Spectrum Analysis;
- Astronomy