Experimental Study of Boron-coated Straws with a Neutron Source

TL;DR

This paper presents an experimental evaluation of boron-coated straw neutron detectors developed as an alternative to 3He detectors, demonstrating promising spatial resolution and neutron-gamma discrimination capabilities for neutron scattering applications.

Contribution

It introduces a new boron-coated straw detector module with a specific readout system and evaluates its performance using a neutron source, addressing 3He shortages.

Findings

Achieved a longitudinal resolution of 6.1-0.5 mm.

Demonstrated effective neutron-gamma discrimination.

Confirmed suitability for neutron scattering spectrometry.

Abstract

Multiple types of high quality neutron detectors are proposed for the first phase of the China Spallation Neutron Source (CSNS), which will be commissioned in 2018. Considering the shortage of 3He supply, a detector module composed of 49 boron-coated straws (BCS) was developed by Proportional Technologies Inc. (PTI). Each straw has a length of 1000 mm and a diameter of 7.5 mm. Seven straws are tightly packed in a tube, and seven tubes are organized in a row to form a detector module. The charge division method is used for longitudinal positioning. A specific readout system was utilized to output the signal and simultaneously encode each straw. The performance of this detector module was studied using a moderated 252Cf source at the Institute of High Energy Physics (IHEP). The signal amplitude spectrum indicates its n-gamma discrimination capability. Despite the complex readout method, a longitudinal resolution of 6.1-0.5 mm was obtained. The three-dimensional positioning ability qualifies this BCS detector module as a promising neutron scattering spectrometer detector.