Signal Processing Model for Radiation Transport

Chambers, D H

关键词: ABSORPTION;    CLASSIFICATION;    COMPTON EFFECT;    DESIGN;    DETECTION;    DISTRIBUTION;    GEOMETRY;    PAIR PRODUCTION;    PHOTONS;    PROCESSING;    RADIATION TRANSPORT;    SHIELDS;    SIMULATORS;    TRANSPORT;   

DOI  :  10.2172/945821
RP-ID  :  LLNL-TR-405952
PID  :  OSTI ID: 945821
Others  :  TRN: US0901245

美国|英语

来源: SciTech Connect

【 摘 要 】

This note describes the design of a simplified gamma ray transport model for use in designing a sequential Bayesian signal processor for low-count detection and classification. It uses a simple one-dimensional geometry to describe the emitting source, shield effects, and detector (see Fig. 1). At present, only Compton scattering and photoelectric absorption are implemented for the shield and the detector. Other effects may be incorporated in the future by revising the expressions for the probabilities of escape and absorption. Pair production would require a redesign of the simulator to incorporate photon correlation effects. The initial design incorporates the physical effects that were present in the previous event mode sequence simulator created by Alan Meyer. The main difference is that this simulator transports the rate distributions instead of single photons. Event mode sequences and other time-dependent photon flux sequences are assumed to be marked Poisson processes that are entirely described by their rate distributions. Individual realizations can be constructed from the rate distribution using a random Poisson point sequence generator.