Large Area Alpha Sources with a Lip: Integral Counting and Spectral Distortions

Published

August 31, 2017

Author(s)

Lynne E. King, Ryan P. Fitzgerald, Ronald Tosh

Abstract

The detection efficiency for large area alpha sources with adjustable heights of a raised lip around the edge were measured by 2π gas-filled proportional counter. The variations in low- energy spectral shape were modeled using a Geant4 radiation and charge transport Monte Carlo simulation, to enable extrapolation of the spectrum to zero energy. Changes in the spectrum gain in the presence of a lip were explored using COMSOL Multiphysics finite-element analysis and qualitatively reproduced an increase in peak height due to an increasing height of the source lip. A spectrum analysis procedure was developed to perform integral counting on sources with a lip. The experimental results were used to validate the model, which was then used to predict the changes in 2π counting efficiency for other source-lip geometries.

Citation

Applied Radiation and Isotopes

Volume

134

Pub Type

Journals

Download Paper

https://doi.org/10.1016/j.apradiso.2017.08.030

Local Download

Keywords

proportional counter, large area sources, source geometry, Monte Carlo

Citation

King, L. , Fitzgerald, R. and Tosh, R. (2017), Large Area Alpha Sources with a Lip: Integral Counting and Spectral Distortions, Applied Radiation and Isotopes, [online], https://doi.org/10.1016/j.apradiso.2017.08.030, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=923092 (Accessed October 19, 2025)