| Just as an excited atom can dispose of its excess energy by emitting x rays, an excited nucleus can emit gamma rays. |
| Visible light is just a small part of a continuum of electromagnetic radiation that extends from radio waves to gamma rays. |
| The decaying atoms emit positrons, which encounter electrons and are annihilated, releasing pairs of gamma rays. |
| After a time the gamma rays are counted by gamma ray sensitive spectrometers. |
| But the very same atmosphere is opaque in most frequencies of far infrared, ultraviolet, x-rays and gamma rays. |
| Unlike in the earlier experiments, the team recorded gamma rays, a revealing product of fusion reactions. |
