Efficiency calibration and coincidence summing correction for a 4πNaI(Tl detector array

被引：30

作者：

Byun, SH ^{[1
]}

Prestwich, WV ^{[1
]}

Chin, K ^{[1
]}

McNeill, FE ^{[1
]}

Chettle, DR ^{[1
]}

机构：

[1] McMaster Univ, Med Phys & Appl Radiat Sci Unit, Hamilton, ON L8S 4K1, Canada

来源：

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT | 2004年 / 535卷 / 03期

关键词：

NaI(Tl) detector; efficiency; coincidence summing; Monte Carlo simulation; in vivo neutron activation;

D O I：

10.1016/j.nima.2004.06.174

中图分类号：

TH7 [仪器、仪表];

学科分类号：

0804 [仪器科学与技术]; 080401 [精密仪器及机械]; 081102 [检测技术与自动化装置];

摘要：

Efficiency calibration and coincidence summing correction were performed for an array of NaI(Tl) detectors developed for in vivo neutron activation analysis. The detector array consisted of eight large NaI(Tl)s with square cross-section and the enclosing geometry of the detection produced both extremely high efficiency and a severe coincidence summing effect. The efficiency was calibrated mainly by Monte Carlo simulation with the EGS4 code. In order to obtain the coincidence summing correction factors through the simulation the coincident emission of photons was modeled. The influence of the angular correlation was explicitly investigated by adding the angle-correlated sampling routine in the simulation code. The experimental efficiencies and correction factors were measured using Cs-137, Co-60 and Na-22. For both peak and total efficiencies, experiment and simulation typically agreed within 5%. The discrepancy between simulation and experiment for the coincidence summing correction factors was 15% or less. The approximate methods adopted in the measurement were analyzed in detail and estimated to be reliable for calibrating high-efficiency detectors. The calculation was finally expanded from point sources to realistic volume sources. (C) 2004 Elsevier B.V. All rights reserved.

引用

页码：674 / 685

页数：12

共 30 条

[1]

Analytical formulae for well-type NaI (Tl) and HPGe detectors efficiency computation [J].