Positron annihilation radiation from the galactic center region
Abstract
Measurements of 0.511 MeV radiation from the vicinity of the galactic center performed by the high resolution gamma ray spectrometer aboard the HEAO 3 spacecraft are discussed. The spectrometer is described and an exploded view of it exhibited, and scans in the 50-244 keV region as well as 0.511 MeV are shown. The intensity from the Crab nebula remained constant while that of the Cygnus source increased considerably, and there was a decrease in the radiation from the vicinity of the galactic center. The flux emanating from the center implies an annihilation rate of 10 to the 43rd per second. The apparent time variation and the spatial extent observed tend to limit the source to a single object and the annihilation region to a size less than about one light year.
- Publication:
-
Annals of the New York Academy of Sciences
- Pub Date:
- December 1981
- DOI:
- 10.1111/j.1749-6632.1981.tb33704.x
- Bibcode:
- 1981NYASA.375..330J
- Keywords:
-
- Astronomical Spectroscopy;
- Galactic Nuclei;
- Galactic Radiation;
- Gamma Ray Astronomy;
- Positron Annihilation;
- Energy Spectra;
- Gamma Ray Spectrometers;
- Heao 3;
- X Ray Astronomy;
- Space Radiation