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arXiv · astro-ph/0109200

The Crab pulsar in the 0.75-30 MeV range as seen by CGRO COMPTEL

Abstract

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.

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L. Kuiper, W. Hermsen, G. Cusumano, R. Diehl, V. Schonfelder, A. Strong, K. Bennett, M. McConnell. 2001-09-13. The Crab pulsar in the 0.75-30 MeV range as seen by CGRO COMPTEL. https://doi.org/10.1051/0004-6361%3A20011256

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