COMPTEL overview: Achievements and expectations.
The Imaging Compton Telescope (COMPTEL) aboard NASA's Compton Gamma-Ray Observatory has opened the 1 to 30MeV γ-ray energy range as a new window to astronomy. The first-ever broadband all-sky maps in this energy range now exist. A variety of γ-ray emitting objects are visible, namely spin-down pulsars, stellar black-hole candidates, supernova remnants, extended regions of interstellar space, nuclei of active galaxies, γ-ray bursts, and the Sun during solar flares. Moreover, the MeV range is rich in γ-ray lines. Here, COMPTEL has achieved a major breakthrough by generating the first all-sky map of the 1.8MeV line from radioactive 26Al. In addition, COMPTEL succeeded in the first detection of the 1.156MeV line from radioactive 44Ti from a supernova remnant (Cas A), and - again for the first time - detected MeV emission from the Orion complex that can be ascribed to nuclear interaction lines from excited 12C and 16O nuclei. Recently, indications of two 56Co lines at 847 and 1.238MeV were found in the measurement of SN 1991T.
Astronomy and Astrophysics Supplement Series
European Southern Observatory (ESO)
V. Schönfelder, K. Bennett, H. Bloemen, R. Diehl, W. Hermsen, G. Lichti, M. McConnell, J. Ryan, A. Strong, and C. Winkler. COMPTEL OVERVIEW: ACHIEVEMENTS AND EXPECTATIONS. 1996, Astron. Astrophys. Suppl., 120, C13.