Standard Article

Activity Determination and Localization of Radioactive Point Source in a Large Medium

Nuclear Methods

  1. Zeev B. Alfassi

Published Online: 29 SEP 2008

DOI: 10.1002/9780470027318.a9022

Encyclopedia of Analytical Chemistry

Encyclopedia of Analytical Chemistry

How to Cite

Alfassi, Z. B. 2008. Activity Determination and Localization of Radioactive Point Source in a Large Medium. Encyclopedia of Analytical Chemistry. .

Author Information

  1. Ben Gurion University, Israel Università degli Studi and INFN of Milano, Segrate, Beer Sheva

Publication History

  1. Published Online: 29 SEP 2008

Abstract

The activity and localization of a small-sized radioactive source in a large medium was studied for various cases by the simultaneous use of several detectors. The γ-emitting source and the neutron-emitting source were both studied. This also led to an α-emitting source, which cannot be detected from outside of the medium unless the neutrons from their (α, n) reaction with low Z elements are detected. A special actual case of commercial lung counter with four semiplanar HPGe detectors is described in detail. For large boxes, NaI(Tl) detectors were used for γ measurements measuring only the full-energy peaks. For neutrons, only thermal neutrons were measured with 3He detectors. To increase the fraction of the thermal neutrons and to protect the measurer, the sample was surrounded by a fence made of 5-cm polypropylene.