Use of Scintillation Counters for Space Radiation Measurements

Scintillation detectors used in space applications must meet rigid criteria for high performance at reduced pressure, at variable temperatures and must withstand extremes of shock and vibration. A large number of tubes have been subjected to shock and vibration tests. Ruggedized tubes withstood the tests and showed little change in gain. Measured temperature coefficients of gain varied from -.19% to -. 53% /°C, from 25°C to 70°C and may be circuit compensated. Battery and inverter type high voltage supplies have shortcomings which have been overcome in a high frequency voltage inverter circuit which supplies potential to each dynode directly. A preamplifier is described which has a voltage gain of one, a high input impedance and wide dynamic range such that further amplification is not required. The techniques described have been tested in several space flights.