Ion processes in a liquid-xenon ionization chamber under high-intensity pulsed irradiation |
| |
Authors: | M A Kirsanov I M Obodovskiy |
| |
Affiliation: | 1.National Nuclear Research University MEPhI,Moscow,Russia |
| |
Abstract: | The current of positive ions in a liquid-xenon ionization chamber was studied under intense pulsed irradiation of the chamber
with bremsstrahlung from a microtron. The dose absorbed in xenon during a radiation pulse was varied from 0.1 to 1.3 × 104 μGy. It has been revealed that, in the dependence of the current on the irradiation dose, a deviation from a simple linear
dependence is observed at a pulse dose of ∼4 μGy (∼0.2D
cr). Calculations show that recombination is the main cause of such deviation. A space charge appearing in the chamber under
high irradiation intensities leads to a decrease in the electric field. The manifestation of the effects of a space charge
becomes substantial when the field in a certain part of the chamber drops almost to zero. Under particular irradiation conditions,
the space charge manifested itself in this study beginning with doses in a pulse of ∼50 μGy. The joint effect of the recombination
and the space charge resulted in a dependence of the type of i ∼ D
1/3. The influence of the ion current on the energy resolution of the ionization spectrometer is calculated for γ quanta detected
during intervals between irradiation pulses. It is shown that a substantial impairment of the resolution begins at doses appreciably
lower than the critical dose. The influence of the ion current becomes greater, as the dimensions of the chamber increase. |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|