High‐energy gamma‐ray astronomy

SEP 01, 1975

The highest‐energy particles and processes in the Universe provide clear and often unique information on the structure and history both of our Galaxy and of the regions beyond.

DOI: 10.1063/1.3069157

Carl Fichtel

Kenneth Greisen

Donald Kniffen

All the natural electromagnetic radiation reaching the Earth, whether from nearby or remote parts of the universe, brings with it information on the contents or structure of the region in which it originated. This is true of each part of the spectrum, from radio waves through the visible, ultraviolet and x‐ray regions, to the realm of high‐energy gamma rays which is our subject here. We will be concentrating on celestial gamma rays, with energies above about 10 MeV, which provide clear and in some respects unique information on the high‐energy particles and processes in the universe, both currently and in the remote past.

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More about the Authors

Carl Fichtel. Senior Scientist of the High Energy Astrophysics Laboratory, Goddard Space Flight Center.

Kenneth Greisen. Physics Department of Cornell University.

Donald Kniffen. Gamma Ray and Nuclear Emulsion Branch of Goddard Space Flight Center.