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.
D006801:Humans; D008838:Microcomputers; D008953:Models, Anatomic; D011874:Radiometry / Q000295:instrumentation*; D011880:Radiotherapy Planning, Computer-Assisted; D013696:Temperature