Observation of a Cosmic Gamma-Ray Burst on Apollo 16. I. Temporal Variability and Energy Spectrum
Abstract
A cosmic gamma-ray event occurring April 27, 1972 at 10.68 UT was observed by gamma-ray and X-ray spectrometers on Apollo 16 as well as by Vela 6A. Analysis has yielded a detailed time profile of the entire event, an energy spectrum covering three order of magnitude (2.0 to 7.9 KeV and 0.067 to 5.1 MeV) and a source location. A well-defined onset prior to the main impulse period and a probable precursor are reported. The total energy of the event over the observed range was 2 x 10 to the minus 4th power ergs/sq cm. The data indicate the presence of a hard component which persists during the entire event, with a softer variable component becoming dominant during the most explosive burst portion.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- November 1974
- DOI:
- 10.1086/181660
- Bibcode:
- 1974ApJ...194L..19M
- Keywords:
-
- Apollo 16 Flight;
- Cosmic Ray Showers;
- Energy Spectra;
- Gamma Rays;
- Periodic Variations;
- X Ray Spectroscopy;
- Bursts;
- Spaceborne Astronomy;
- Spacecraft Instruments;
- Time Response;
- Space Radiation