Abstract
IN view of the pulsar ‘glitches’, the optical activity, and the multi-component nature of its radiation1,2, there must be a level of sensitivity at which it becomes an oversimplification to state that a constant intensity and single spectral index characterise the total X-ray emission from the Crab Nebula. Here we present spectra of the total nebula and NP0532 obtained in the 15 to 300 keV range during balloon flights on September 9 and 25, 1970. These spectra are both statistically and systematically more accurate than previous hard X-ray measurements, and together with other data show previously unknown or uncertain spectral features.
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LAROS, J., MATTESON, J. & PELLING, R. X-ray Spectral Features of the Crab Nebula and NP0532. Nature Physical Science 246, 109–111 (1973). https://doi.org/10.1038/physci246109a0
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DOI: https://doi.org/10.1038/physci246109a0
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