Theoretical calculations and creation of a composite shadow protection for the CRD detector and a therapeutic channel for a neutron generator

Theoretical calculations for the multilayer protection of a digital imaging detector (DDI) have been carried out. After analyzing the obtained attenuation coefficients of the calculated composite protection, its application for the formation of a neutron channel is proposed. The principle of operation of a multifunctional ionization chamber (MIC) for recording profiles of pulsed conditional spots from a neutron generator is considered. The principle of operation of the MIC chamber is based on the interaction of integrating electrodes and sensor cells. Sensor cells consist of 16 pads, the signals from which arrive in a pulsed mode synchronously with the incoming trigger signal. The 16 channel integrator board 1 board processes the input signals and sends them to the Deviation Detection Control Circuit (DDS). If the COOS circuit detects a deviation from the specified parameters, it immediately turns off the neutron generator (NG). A schematic diagram of a 16-channel charge-sensitive amplifier that exchanges information between the MIC camera and a computer is considered. Timing diagrams of the passage of signals are given on the example of one channel 1 board. The MIC chamber, together with the neutron beam channel and multilayer shielding, is designed for neutron therapy. Variants of composite multilayer protection of a medical channel based on a neutron source based on the NG-24 neutron generator are proposed. The channel design is built on the basis of Monte Carlo calculations on the example of selected protective materials - water, tivarobor and tungsten. A patent is considered, on the basis of which it is proposed to design a composite shadow protection of a neutron therapeutic channel. It is proposed to use the MIC chamber to control the dose profiles of neutron beams.

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