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Event Identification in He-3 Proportional Counters Using Risetime Discrimination
Published
Author(s)
Jeffrey S. Nico, T J. Langford, Christopher D. Bass, E J. Beise, D. K. Erwin, Craig Heimbach
Abstract
We present a straightforward method for particle identification and background rejection in He-3 proportional counters for use in neutron detection. By measuring the risetime and pulse height of the preamplifier signals, one may define a region in the risetime versus pulse height space where the events are predominately from neutron interactions. For the proportional counters used in this study, there is an alpha-particle rejection of 96%. By applying the same method, we also show an effective rejection of microdischarge noise events that, when passed through a shaping amplifier, are indistinguishable from physical events in the counters. The primary application of this method is in measurements where the signal-to-background for counting neutrons is very low, such as in underground laboratories.
Nico, J.
, Langford, T.
, Bass, C.
, Beise, E.
, Erwin, D.
and Heimbach, C.
(2013),
Event Identification in He-3 Proportional Counters Using Risetime Discrimination, Nuclear Instruments & Methods in Physics Research, [online], https://doi.org/10.1016/j.nima.2013.03.062
(Accessed October 6, 2025)