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We present the time-averaged characteristics of the Crab pulsar in the 0.75-30 MeV energy window using data from the imaging Compton Telescope COMPTEL aboard the Compton Gamma-Ray Observatory (CGRO) collected over its 9 year mission. Exploiting the exceptionally long COMPTEL exposure on the Crab allowed us to derive significantly improved COMPTEL spectra for the Crab nebula and pulsar emissions, and for the first time to accurately determine at low-energy gamma-rays the pulse profile as a function of energy. These timing data, showing the well-known main pulse and second pulse at a phase separation of 0.4 with strong bridge emission, are studied together with data obtained at soft/hard X-ray energies from the ROSAT HRI, BeppoSAX LECS, MECS and PDS, at soft gamma-rays from CGRO BATSE and at high-energy gamma-rays from CGRO EGRET in order to obtain a coherent high-energy picture of the Crab pulsar from 0.1 keV up to 10 GeV.
We report on a study of the gamma-ray continuum emission from the Crab supernova nebula and on a search for nuclear de-excitation gamma-ray lines. Crab is the brightest continuum source in the 1-10 MeV gamma-ray sky, and its continuum radiation is mo
The COMPTEL experiment aboard the Compton Gamma-Ray Observatory (CGRO) has observed the gamma-ray blazar 3C 279 several times between April 1991 and September 1995. This paper reports on a consistent analysis of these observations using the most rece
Neutron stars generate powerful winds of relativistic particles that form bright synchrotron nebulae around them. Polarimetry provides a unique insight into the geometry and magnetic configuration of the wind, but high-energy measurements have failed
The COMPTEL observations of the blazar-type quasar PKS 0528+134 in the energy range 0.75 MeV to 30 MeV carried out between April 1991 and September 1994 have been analyzed. During the first two years PKS 0528+134 was most significantly detected at en
COMPTEL was the Compton telescope on NASAs Compton Gamma Ray Observatory CGRO launched in April 1991 and which was re-entered in June 2000. COMPTEL covered the energy range 0.75 to 30 MeV, and performed a full-sky survey which is still unique in this