After-Pulses in a GM-Counter Caused by Radiations from Radioactive Nuclide

A method of increasing the counts for a random source in an organic-quenched GM-counter is reported. A large increase in counting rate was observed when the wire-potential was lowered succeeding the occurrence of a Geiger-discharge. A distinct peak in counting rate exists against the variation of the wire-potential. Even under such conditions that the great increase is induced, the counting rate is dependent on the intensity of the incident rays. Negative ions are proposed as being the dominant factor in this phenomenon.