A regular pulsation in the X-ray flux from A 1540-53.
Abstract
An analysis of Ariel V quadrant-mode data obtained when the source 3U 1538-52 was within the field of view of the collimated proportional counter is described. The results are shown to indicate the presence of another, substantially weaker source designated A1540-53. It is found that this weaker source has a hard power-law spectrum with a number exponent of approximately -1.1 and exhibits a clear modulation at a period of about 8.81 min. The pulsed fraction is determined to be 25% of the total flux in the energy band from 1.8 to 5.6 keV.
- Publication:
-
Monthly Notices of the Royal Astronomical Society
- Pub Date:
- April 1977
- DOI:
- 10.1093/mnras/179.1.35P
- Bibcode:
- 1977MNRAS.179P..35D
- Keywords:
-
- Energy Spectra;
- Periodic Variations;
- Satellite Observation;
- X Ray Sources;
- Ariel 5 Satellite;
- Energy Bands;
- Galactic Radiation;
- Light Curve;
- Power Spectra;
- Proportional Counters;
- Radiant Flux Density;
- X Ray Spectra;
- Astrophysics