COMPTEL upper limits to MeV emission from the globular cluster 47 Tucanae
The nearby globular cluster 47 Tucanae was observed by the CGRO COMPTEL instrument for several weeks during 1991 to 1993. These observations yield no evidence for MeV γ-ray emission from this object, giving upper limits lower than previous measurements. From our MeV emission constraint, we place upper limits to the MeV photon flux from known millisecond pulsars in this globular cluster. We also estimate the maximum number of ablating objects (similar to PSR B1957+20) in the cluster, and the number of hidden millisecond pulsars.
Astronomy and Astrophysics
European Southern Observatory (ESO)
K.S. O'Flaherty, K. Bennett, R. Diehl, W. Hermsen, M. McConnell, V. Schönfelder, and C. Winkler. COMPTEL UPPER LIMITS TO MEV EMISSION FROM THE GLOBULAR CLUSTER 47 TUCANAE. 1995, Astron. Astrophys., 297, L29.