METHOD AND SYSTEM FOR RECOVERING SCINTILLATION PULSE INFORMATION

摘要

A method for recovering scintillation pulse information. The method comprises the steps: obtaining a scintillation pulse database of unstacked compliance single-events in a low count, and establishing a noise model of a scintillation pulse for the scintillation pulse database of the single-events; calculating a posterior probability logarithm value of a specific energy value according to the noise model of the scintillation pulse; and repeatedly calling the second step by means of calculations, and obtaining an energy value meeting a maximum posterior probability condition. A system for recovering scintillation pulse information. The system comprises a fluctuation model module, a posterior probability module, and an energy value search module. The method and system for recovering scintillation pulse information in the present invention effectively improve the precision of a system energy calculation, and is specifically suitable for an energy calculation of a sparse quantization level ADC digital nuclear instrument.

主权项

1. A method for recovering scintillation pulse information, comprising:
step S1: acquiring a scintillation pulse database of non-stacked compliance single events in a low count, and building a scintillation pulse noise model for the scintillation pulse database of the single events, wherein an average pulse is calculated for the scintillation pulse database of the non-stacked compliance single events, and scintillation pulse shape information is given by the average pulse; step S2: calculating a posterior probability logarithm value for a given energy value based on the scintillation pulse noise model, comprising:
step 2.1: loading a scintillation pulse segment S0, and calculating a likelihood function of the given energy value based on the pulse noise model, wherein the scintillation pulse segment starts at a time point t0 at which the scintillation pulse segment passes upwards a threshold v1, and the scintillation pulse segment ends at a time point t0+Δt, with Δt being greater than two times of a time constant of a falling edge of a scintillation crystal; andstep 2.2: calculating logarithms for all of the time points and adding up the logarithms, to obtain a value of a function having same monotonicity as a posterior probability function; and step S3: performing step S2 repeatedly to obtain an energy value meeting a maximal posterior probability condition, comprising:
step 3.1: calculating posterior probabilities for different tentative energy values by repeatedly performing step S2 as a module;step 3.2: searching linearly for the energy value meeting the maximal posterior probability condition; andstep 3.3: after the energy value is obtained, correcting a time origin for step 2.1 based on the energy value and repeating step 3.1 and step 3.2.