Astronomy   View all facts   Glossary   Help | 
| physical object > natural object > particle > boson > carrier boson > photon > gamma ray > hard gamma ray | 
| hard gamma ray comparison table | ||
| Subject | is a kind of | has definition | 
|---|---|---|
| gamma ray | photon | Photon of very high frequency (wavelength shorter than a few tenths of an angstrom); the most energetic form of electromagnetic radiation, although there is no sharp boundary between γ-ray photon and an X-ray photon. Usually γ-ray photons come from the nucleus and X-ray photons come from the inner orbital electrons. Galactic γ-ray photons seem to originate primarily in the spiral arms. | 
| hard gamma ray | gamma ray | 
 Up: gamma ray