Large-area nuclear radiation detector

摘要

In the novel nuclear radiation detector, a proportional counting tube (4) and a fast ionisation chamber (3) with its large areas are arranged side-by-side in a common gas chamber. The counting tube is operated with a pronounced gas amplification, the ionisation chamber has a gas amplification of 1. Seen in the incident radiation direction, the ionisation chamber has such a depth that alpha radiation of the energy of maximum interest is provided with a gas path which is adequate for total absorption. The proportional counting tube is operated at a high voltage of approximately two kilovolts, but the ionisation chamber is operated at a voltage of only 200 volts. As a result of this arrangement, excellent separation is achieved in the measurement of alpha particles on the one hand and beta radiation and gamma radiation on the other hand. At the same time, energy-selective evaluation of the alpha particles is possible. IMAGE