SIGMA Upper Limits to the Hard X-Ray/Soft Gamma-Ray Emission from the Millisecond Pulsars of the Nearby Globular Cluster 47 Tucanae
Abstract
Upper limits to the hard X-ray/soft gamma-ray emission from the millisecond pulsars of the nearby globular cluster 47 Tucunae are determined on the basis of observations performed by the SIGMA telescope aboard the GRANAT spacecraft. The SIGMA upper limits are also compared with the high-energy fluxes predicted from theoretical models of the well-known ablating millisecond pulsar PSR 1957+20, which makes it possible to place upper limits on the number of objects similar to PSR 1957+20 in 47 Tuc.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- March 1993
- DOI:
- 10.1086/186765
- Bibcode:
- 1993ApJ...405L..59B
- Keywords:
-
- Gamma Ray Astronomy;
- Globular Clusters;
- Pulsars;
- X Ray Astronomy;
- Milky Way Galaxy;
- Spaceborne Astronomy;
- Astrophysics