Low Voltage He3-Filled Proportional Counter for Efficient Detection of Thermal and Epithermal Neutrons

1 August 1962

journal article
research article
Published by AIP Publishing in Review of Scientific Instruments

Vol. 33 (8) , 866-868
https://doi.org/10.1063/1.1717994

Abstract

Neutron counters using He³ gas at absolute pressures up to 10 atm have been constructed and tested. The relative detection efficiency for thermal, epicadmium, and fast neutrons was measured as a function of pressure from 1 to 10 atm, and compared with similar data from a boron trifluoride counter of the same size filled to a pressure of 65 cm of B¹⁰F₃ gas. The ratio He³/BF₃ increases approximately linearly with pressure for epicadmium and fast neutrons, reaching values of 26.6 and 21.6, respectively, at 10 atm He³ pressure. This ratio shows a saturation effect for thermal neutrons, becoming 4.45 at 10 atm He³ pressure. The gamma‐ray response has been found to be low with proper pulse shaping. High voltage plateau curves for 3‐ and 7‐atm counters are given and indicate operating regions at least 100 V wide at a counter high voltage of about 1200 V.

Keywords

This publication has 4 references indexed in Scilit:

Interaction of Neutrons with ${He}^{3}$
Physical Review B, 1961
Helium-3 Filled Proportional Counter for Neutron Spectroscopy
Review of Scientific Instruments, 1955
Neutron Energy Measurements with a Helium 3 Filled Proportional Counter
Proceedings of the Physical Society. Section A, 1952
A Neutron Detector Having Uniform Sensitivity from 10 Kev to 3 Mev
Physical Review B, 1947