Gamma-Ray Lines Produced by Low-Energy Cosmic Rays in SN 1987A
Abstract
The ^56^Fe nuclei excited by the inelastic collision of protons with the energy of around 10 MeV emit gamma rays in the same nuclear gamma-ray lines as those from the radioactive decay of ^56^Co. Since a very young supernova remnant like SN 1987A is most likely to accelerate cosmic rays by the shock and a possible pulsar embedded in the ejecta, this process may account for the gamma-ray lines observed from SN 1987A. We have investigated the conditions required to explain the observed flux of the gamma-ray lines. We found that this process requires a nonspherical distribution of the ejecta so strong as to produce a well-collimated cosmic-ray jet having a large fraction of the total kinetic energy of the supernova explosion.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- May 1989
- DOI:
- 10.1086/167449
- Bibcode:
- 1989ApJ...340..950E
- Keywords:
-
- Cosmic Rays;
- Gamma Ray Astronomy;
- Gamma Ray Spectra;
- Supernova 1987a;
- Cosmic X Rays;
- Emission Spectra;
- Iron Isotopes;
- Particle Acceleration;
- Pulsars;
- Radioactive Isotopes;
- Astrophysics;
- COSMIC RAYS: GENERAL;
- GAMMA RAYS: GENERAL;
- STARS: INDIVIDUAL ALPHANUMERIC: SN 1987A;
- STARS: SUPERNOVAE