DEPRON device (Dosimeter of Electrons, PROtons and Neutrons) is intended for the measurements of the absorbed doses and linear energy transfer spectra from high-energy electrons, protons and nuclei of space radiation, and for detecting of thermal and slow neutrons flux.
What’s an idea of the measurement method?
The device includes:
- Charged particles dosimeter based on semiconductor detector
- Thermal neutrons detector based on gas-discharge counter SI13N
- Circuits for analogous and digital processing of detectors’ signals, for information storage and analysis
- Power supply units for the detectors and electronics
Charged particles detector is based on semiconductor one. For each detected particle an amplitude of impulse proportional to the energy lost by the particle in the detector’s track sensitive volume is registered. The value of the absorbed radiation dose is determined by summarizing of all the values of energy losses in the detector’s active zone and normalizing it by the mass of this zone.
Two semiconductor detectors each connected to its personal channel of analogous signal development are used for reliability. Besides, the detectors are disposed in sequence and operated with coincidence unit, which allows to use them as detector telescope. Registration of energy loss spectrum for the particles produced signals in both detectors allows to evaluate ionization losses spectrum for such particles.
Gas-discharge counter SI13N operated in a stable corona mode is used for thermal neutrons registration. Counter’s operation is based on the following reaction between neutrons and He-3 filling the chamber: n+3He = p+T+764 КэВ.
Two counters SI13N are used for reliability by analogy with semiconductor unit. One counter is covered with moderator (organic glass) in order to widen sensitive zone into the slow neutrons area.
Parameters of the device and measured parameters
Dimensions 280x160x78 mm, Mass – 3.0 kg
The ranges of the parameters measured by means of semiconductor detectors:
- Absorbed dose, Gy 10-5 – 10+1
- Absorbed dose rate, Gy/hour 10-6 – 10-1
- Flux density, part /(cm2 s) 1 – 104
- Ionization losses of the particles, for which energy losses spectrum must be determined of 2 to 430, MeV/(g cm-2)
The ranges of the parameters, measured by means of SI13N counters – neutron flux density for the neutrons within energy ranges of 10-3 – 10 2 eV is 0.1 – 102 neutrons / (cm2 s).