Pulse shape discrimination of plastic scintillator EJ 299-33 with radioactive sources

Abstract

The present study has been carried out in order to investigate about the possibility of using EJ 299-33 scintillator in a multi-detector array to detect neutrons along with light charged particles. In a reaction induced by stable and exotic heavy-ions beams, where copious production of neutrons and other light charged particles occurs, discrimination with low identification threshold of these particles are of great importance. In view of this, EJ 299-33 scintillator having dimension of 3 cm × 3 cm × 3 cm backed by a photomultiplier tube was tested and used under vacuum to detect neutrons, gamma-rays and alpha particles emitted by radioactive sources. Anode pulses from the photomultiplier tube were digitized through GET electronics, recorded and stored in a data acquisition system for the purpose of an off-line analysis. The measurements, under vacuum and low background conditions, show good pulse shape discrimination properties characterized by low identification threshold for neutrons, gamma-rays and alpha particles. The Figures of Merit for neutron-gamma and alpha particles-gamma discriminations have been evaluated together with the energy resolution for gamma-ray and alpha particles.

The NArCoS Project: The Latest Results

“…The EJ 299-33 scintillator was optically coupled to a quartz window photomultiplier tube (PMT) 9514B manufactured by EMI operated at a bias of 1.7 KV. A good linearity in the energy calibration [4,6] was achieved. The output signal from the PMT detector was digitized by GET (General Electronics for TPC) electronics [8], using a sampling frequency of 100 MHz.…”

“…The EJ299-33 plastic scintillator cell has been tested both in low-background condition [4] and high-background conditions [6]. In the first case the plastic -neutron pulse shape discrimination (PSD) capabilities were tested by using 60 Co -source, 241 Am and 228 Th -sources and AmBe source for neutron and .…”

“…Since the EJ276 plastic scintillator is able to discriminate neutron, and charged particles (see next subchapter) [4] we plan to use a Double Sided Silicon Strip Detector (DSSSD) of 300 m of thickness as veto detector in order to distinguish primary neutrons against primary protons or other light charged particles. The DSSSD (placed at some distance, see Fig.…”

“…In brief, we will present a preliminary research proposal aimed at developing a first prototype of multi-element plastic-scintillator (16 detection modules by assembling 64 elementary detection cells) able to detect neutrons in coincidence with LCPs and IMFs with both good angular and energy resolution, by supporting reasonable efficiency. One candidate that is suggested for this purpose is an array of plastic scintillators EJ-276 (ex-EJ-299-33) [4,5,6,7].…”

Compact MPPC-based coded aperture imaging camera for dual-particle detection

“…It has the nearly equivalent performance of liquid organic scintillators without the toxicity and frangibility. Photomultiplier tubes (PMT), as a mature photoelectric converter, are commonly used to couple with the scintillator array to detect the gamma rays or neutrons [8][9][10][11][12][13][14][15][16][17][18][19]. The fluorescence for several pixelated plastics was detected by a single PMT, which led to poor position resolution and high noise.…”