Counts per minute

Counts per second ( dt counts or counts per second ), short cps, a measure of the count rate ( the average repetition frequency of measurement signals which are counted as temporally separate individual events). Analogous to the unit counts per second is the unit of counts per minute (cpm ) defined.

Use

An event in this sense is usually the registration of a photon, electron or other particle by a particle detector. The unit is widely used in atomic and nuclear physics and in many applications, such as X-ray induced photoelectron spectroscopy ( XPS) and Auger electron spectroscopy (AES ) and used in nuclear medicine.

Demarcation

The unit cps is in principle equivalent to the units of hertz (Hz ); Hz is typically used for periodic processes, cps, however, for time randomly distributed counts ( the number of events per unit of time usually follows a Poisson distribution ).