noun
disintegration per minute; dpm
Technical term in physics for the number of radioactive decays occurring in one minute.
この試料の放射能は約500壊変毎分です。
The radioactivity of this sample is about 500 disintegrations per minute.
Compound of 壊変 (kaihen, 'disintegration') and 毎分 (maifun, 'per minute').