Method and device for generating bremsstrahlung with a pulse-to-pulse variation in energy level between two given values

Abstract

The invention relates to a method and a device, which can be used in inspection systems, for generating bremsstrahlung with a pulse-to-pulse variation in energy level between two given values with the possibility of independently controlling the radiation intensity for each energy level. The device has local radiation shielding (16) and provides for a small diameter beam on the braking target (12) as well as highly efficient particle acceleration. The device comprises an accelerator structure (7) with a standing wave, which is powered by a compact multibeam klystron (22) having a low beam voltage and permanent magnet focusing. The energy level of an accelerated beam (19) of charged particles is varied at a constant frequency by varying the output power level of the klystron (22) from pulse to pulse and the amplitude of the field in the accelerator structure (7). The required radiation intensity is provided by the pulse-to-pulse variation of the voltage of the control electrode (10) of an electron gun (8) and of the current intensity of the beam injected into the accelerator structure (7).

Description

technical field [0001] The invention relates to an acceleration device for a detection system. The acceleration device is based on an accelerator that realizes pulsed bremsstrahlung adjustable between two energy levels with an energy-adjustable beam of charged particles, and adopts pulsed generation and acceleration technology of charged particles , the invention also relates to the construction of linear accelerators for such purposes. Background technique [0002] Linacs, which produce pulsed beams of charged particles, are widely used in customs inspection systems to inspect large containers. In such detectors, a beam of charged particles is focused on a decelerating target located at the end of the accelerator. After leaving the collimator, the charged particle beam is strictly collimated into a narrow beam in the direction of the object being inspected. The portion of the beam that has passed the object is registered by a set of detectors. Signals from these detector...

AI Technical Summary

Problems solved by technology

[0044] Experts in charged particle beam physics understand that in all the above-mentioned methods of generating bremsstrahlung and the equipment used for such generation, one should either adjust the frequency of the high-frequency power supply or use two sources with different frequencies, which leads to excessive Complexity and reduced reliability, and the use of conventional klystrons is accompanied by the use of solenoids and high-voltage power supplies with voltages exceeding 100kV, resulting in nothing but increased mass and size

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