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Event Identification in He-3 Proportional Counters Using Risetime Discrimination



Jeffrey S. Nico, T J. Langford, Christopher D. Bass, E J. Beise, D. K. Erwin, Craig Heimbach


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.
Nuclear Instruments & Methods in Physics Research


He-3, neutron detection, proportional counters


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], (Accessed May 21, 2024)


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Created April 2, 2013, Updated November 10, 2018