Monte Carlo Simulation Of Vacuum Compton Detector

Vacuum Compton Detector(VCD)has been used to measure intense and pulsed gamma for a long time.It has advantages such as fast,linear response and wide dynamic range.It can be used in the applications which involve a wide range of gamma ray energy as its sensitivity is subjected to very small change over that wide range.VCD has a simple structure,including an emitter,front window,rear window and a cylindrical air proof casing.Different structure and material design lead to different sensitivity.This thesis focuses on sensitivity of VCD affected by a number of design factors of material and structure.For the gamma ray with energy of 1.25 MeV,we calculate the quantum efficiency for forward electrons and backscatter efficiency with different materials using Monte Carlo software,and determine which materials are suitable for higher sensitivity.The sensitivity of VCD is subject to variation for a number of factors such as collimator's diameter,front window's thickness,the placement of its emitter plate with respect to the front window and distance between two emitter in case of dual emitter VCD,which has been observed in simulations performed in MCNP,we obtain the reasonable and optimal design construction and parameters.The research results supply theoretical basis and technology support for development of advanced radiation design.