Real-time pulse shape discrimination for neutron scattering science using EJ-270. (1st August 2022)

• Record Type: Journal Article
• Authors: Richards, S.A.; Helbsy, W.; Sykora, G.J.; Wheater, R.M.; Wilson, M.D.
• Is Part Of: Journal of instrumentation. Volume 17:Number 8(2022)
• Publication Date: 2022-08-01
• Subjects: Detector control systems (detector and experiment monitoring and slow-control systems, architecture, hardware, algorithms, databases) -- Digital signal processing (DSP) -- Neutron detectors (cold, thermal, fast neutrons) -- Scintillators, scintillation and light emission processes (solid, gas and liquid scintillators); Scientific apparatus and instruments -- Periodicals; 502.84
• DOI: 10.1088/1748-0221/17/08/P08011
• Languages: English
• ISSNs: 1748-0221

Abstract

Abstract: A detector for neutron scattering applications utilizing the 6 Li loaded pulse shape discrimination scintillator EJ-270 was developed. The detector utilises a pulse shape discrimination algorithm developed for high-count rate applications implemented in FPGA to enable real time operation. The implemented algorithm we call Tail Sum was specifically developed for high-rate thermal neutron detection and implemented into a 2 channel 500 MSps 14-bit ADC with a Xilinx Kintex 7 K325T FPGA. The detector consisted of a 48 mm diameter × 15 mm thick cylinder of EJ-270 mounted on a Hamamatsu R6231-100 PMT and an E1198-2 base at -1000 V. The performance of the system was evaluated using a moderated 241 Am-Be mixed radionuclide source, a figure of merit of 1.605 ± 0.007 was measured. The γ-ray sensitivity of the system was measured using a 60 Co source and found to be 3.23 × 10 -6 ± 7 × 10 -8 . The high neutron count rate capability of the system was tested on the Emma instrument at the ISIS pulsed neutron and muon source based at the Rutherford Appleton Laboratory, a peak count rate of 5 × 10 5 neutrons per second was measured on a single channel and was found to have no statistically significant deviation from the expected count-rate.