The high-energy X-ray spectrum of the Crab Nebula observed from OSO-8.
Abstract
Results are reported for a measurement of the X-ray spectrum of the Crab Nebula over the energy range from 20 to 500 keV with a scintillation spectrometer aboard the OSO-8 satellite. A time-averaged spectrum of the nebula is presented which includes the average intensity of the X-ray pulsar NP 0532. The photon spectrum is shown to be well-fitted by a power law with a constant of approximately 4.19, a weighted mean energy of 39.1 keV, and a spectral index of about 2.00. No evidence is found for day-to-day variations in the spectrum of the source. The spectrum obtained is taken as evidence for the single power-law character of the Crab Nebula spectrum out to at least 200 keV and probably to as high an energy as 500 keV.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- November 1977
- DOI:
- 10.1086/155628
- Bibcode:
- 1977ApJ...217..809D
- Keywords:
-
- Astronomical Spectroscopy;
- Crab Nebula;
- Oso-8;
- X Ray Spectra;
- Emission Spectra;
- Photons;
- Pulsed Radiation;
- Spectrometers;
- Statistical Analysis;
- Steady Flow;
- Astrophysics