The SI unit for counts per second is the becquerel (Bq).
While "counts per second" (cps) describes the rate at which events are detected (often by a device like a Geiger counter), the becquerel is the formally defined SI unit for radioactivity, representing one disintegration (or decay) event per second. Therefore, a measurement in counts per second can be related to becquerels, but the relationship depends on the detection efficiency and geometry of the measuring instrument.
- Becquerel (Bq): Defined as one disintegration per second. It is the SI unit of activity, measuring the rate at which a radioactive substance decays. This decay results in the emission of particles or photons.
- Counts Per Second (cps): Represents the rate at which a detector registers events. The count rate depends on factors such as detector efficiency, source geometry, and background radiation. It's the raw output of a measurement device.
Essentially, a Geiger counter might register "counts per second," but the actual radioactivity of the sample is expressed in becquerels. The conversion factor between cps and Bq depends on the specific measurement setup.
