Skip to main content
U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Monte Carlo based approach to the LS-NaI ß-γ anticoincidence extrapolation and uncertainty

Published

Author(s)

Ryan P. Fitzgerald

Abstract

The β-γ anticoincidence method is used for the primary standardization of β-, β+, electron capture (EC), α, and mixed-mode radionuclides. Efficiency extrapolation using one or more γ ray coincidence gates is typically carried out by a low-order polynomial fit. The approach presented here is to use a Geant-based Monte Carlo simulation of the detector system to analyze the efficiency extrapolation. New code was developed to account for detector resolution, direct γ ray interaction with the PMT, and implementation of experimental β-decay shape factors. The simulation was tuned to 57Co and 60Co data, then tested with 99mTc data, and used in measurements of 18F, 129I, and 124I. The analysis method described here offers a more realistic activity value and uncertainty than those indicated from a least-squares fit alone.
Citation
Applied Radiation and Isotopes
Volume
109

Keywords

beta-gamm, anticoincidence, coincidence, Monte Carlo

Citation

Fitzgerald, R. (2015), Monte Carlo based approach to the LS-NaI ß-γ anticoincidence extrapolation and uncertainty, Applied Radiation and Isotopes, [online], https://doi.org/10.1016/j.apradiso.2015.11.107 (Accessed March 28, 2024)
Created November 1, 2015, Updated November 10, 2018