Физика Низких Температур: Том 47, Выпуск 4 (Апрель 2021), c. 335-341 ( к оглавлению , назад )
Long-term stability of TVO low-temperature sensors before and after gamma irradiation with a high dose
Yu. P. Filippov and V. M. Miklyaev
Joint Institute for Nuclear Research, Dubna 141980, Russia
V. V. Vainberg
Institute of Physics, National Academy of Sciences of Ukraine, Kiev 03680, Ukraine
Received October 15, 2020, published online February 26, 2021
The long-term stability of well-known TVO sensors before and after gamma irradiation was investigated duringalmost 17 years. Five of six sensors, calibrated in the temperature range from 3 to 300 K, were selected according to a requirement of their relative accuracy ∆T/T ≤ ±0.25 % at the cryogenic temperature range. Long-term stability measurements made 7.5 years after calibration are in good agreement with this value at 293, 77.3, and 4.2 K. Then these sensors and the sixth sensor, taken as the “worst” one for comparison, were irradiated by the 60Co gamma source at room temperature up to the total dose of about 1 MGy. Noticeable relative temperature shifts (more than ± 0.25 %) are revealed for all the sensors after irradiation, and this fact is explained based on the model of structural changes in the volume of the sensitive element. Post-irradiation measurements carried out during 9 years at 293, 77.3, and 4.2 K indicate good stability of the sensors after irradiation.
Key words: TVO temperature sensor, low temperature, composite carbon material, gamma irradiation, radiation resistance.