Studies in Pulse Shape Discrimination for an Optimized ASIC Design

TL;DR

This study evaluates pulse shape discrimination capabilities using SiPMs and scintillators, providing data to guide the design of a low-cost, low-power ASIC for neutron and gamma detection across a range of energies.

Contribution

It offers experimental insights into scintillator and SiPM performance for PSD, informing the design parameters of a new ASIC for radiation detection.

Findings

Both Stilbene and EJ-276 scintillators are effective for PSD from 100 keV to several MeV.

Optimized integration periods improve PSD performance.

Results guide ASIC design for low-cost, low-power radiation sensors.

Abstract

The continued advancements of Silicon Photomultipliers (SiPMs) have made them viable photosensors for low recoil energy Pulse Shape Discrimination (PSD) between fast neutron and gamma interactions when coupled to an appropriate scintillator. At the same time, the large number of channels in a typical array calls for the development of low-cost and low-power electronics. A custom integrated circuit (ASIC) is an ideal solution for this purpose. To assess the requirements for such an ASIC, studies were performed using two scintillators, Stilbene and EJ-276, coupled to a 6 x 6 mm SiPM from Onsemi. We demonstrate that both scintillators are viable for performing PSD for interaction energies from 100 keV to several MeV while optimizing the integration periods used in the PSD metric. These measurements inform the design parameters of the ASIC under development.