Evidence for the binary nature of A 0535+26.
Abstract
The transient X-ray source A0535+26 was observed extensively with the SAS-3 satellite on two occasions. Sufficient timing data on the 104-s periodicity were obtained to indicate that the pulse period was changing during both of the observations. The possibility that these period changes are intrinsic to the compact star (e.g., due to accretion torques) cannot be completely excluded. However, it is demonstrated that all of the SAS-3 timing data can be explained by orbital motion of the X-ray star about a companion. Constraints are then placed on the orbital elements of the system. The results indicate a model for this source that consists of a neutron star in a long-period orbit (period of at least 17 days) about an OB star with a variable stellar wind.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- September 1976
- DOI:
- 10.1086/182246
- Bibcode:
- 1976ApJ...208L.119R
- Keywords:
-
- Binary Stars;
- Neutron Stars;
- Orbital Elements;
- Stellar Luminosity;
- X Ray Astronomy;
- X Ray Stars;
- Circular Orbits;
- Sas;
- Spaceborne Astronomy;
- Stellar Winds;
- Variable Stars;
- X Ray Sources;
- Astrophysics