Nature 240, 221 - 224 (24 November 1972); doi:10.1038/240221a0

Detection of 10−100 MeV -Rays from the Crab Nebula Pulsar NP 0532

P. ALBATS^*, G. M. FRYE jun.^*, A. D. ZYCH^*, O. B. MACE^†, V. D. HOPPER^† & J. A. THOMAS^†

^*Case Western Reserve University, Cleveland, Ohio 44106
^†Physics (RAAF) Department, University of Melbourne, Melbourne

Pulsed -ray emission from NP 0532 has been detected up to 100 MeV. For the main pulse from 10 to 30 MeV the signal to noise is (5−6). The energy spectrum of the main pulse from 1 keV to 100 MeV can be fitted by a single power law of index (-0.9).

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