GAMMA RAY DETECTOR

摘要

A gamma detector (10) comprises a sealed electrically conductive enclosure (11) defining a cavity (11a) filled with a gas, and with signal collection means (12) insulatively mounted in the cavity (11a) and positioned to substantially span the cavity (11a) so that gas ions generated in the cavity (11a) as a result of gamma ray interaction are electrostatically captured by the signal collection means (12) when an electric potential is applied between the electrically conductive enclosure (11) and the signal collection means (12). Indicator means (19) are attached to the signal collection means (12) for indicating an electrical current produced by collection of gas ions generated in the cavity (11a) by gamma rays in the cavity (11a). A voltage source (18) is connected between the indicator means (19) and the electrically conductive enclosure (11) to provide the electrical potential for collection of the gas ions.