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arXiv · 1212.4724

Event Identification in $^3$He Proportional Counters Using Risetime Discrimination

T. J. Langford·C. D. Bass·E. J. Beise·H. Breuer·D. K. Erwin·C. R. Heimbach·J. S. Nico
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Abstract

We present a straightforward method for particle identification and background rejection in $^3$He 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 six proportional counters surveyed in a low-background environment, we demonstrate the ability to reject alpha-particle events with an efficiency of 99%. 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.

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T. J. Langford, C. D. Bass, E. J. Beise, H. Breuer, D. K. Erwin, C. R. Heimbach, J. S. Nico. 2012-12-19. Event Identification in $^3$He Proportional Counters Using Risetime Discrimination. https://doi.org/10.1016/j.nima.2013.03.062

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