annihilation radiation
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annihilation radiation
[ə‚nī·ə′lā·shən ‚rād·ē′ā·shən] (particle physics)
Electromagnetic radiation arising from the collision, and resulting annihilation, of an electron and a positron, or of any particle and its antiparticle.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.