About the rate of temperature changes in a thimble chamber.

The rate of temperature changes was studied in a nylon thimble chamber provided with a temperature sensor, when the chamber was inserted in different phantom media. It was found, that the temperature time constant for the changes ranged from 40 s (chamber in water) to 515 s (chamber with build-up cap in air). It was also found, that handling the detector for about 30 s caused a temperature rise of about 1 degree C. This temperature rise was reflected in dose-rate measurements with a graphite ionization chamber, but was not measurable with a nylon chamber.