Development of an array of liquid-scintillator-based bar detectors: SABRE*

Advanced neutron detectors will play a key role in future measurements involving radioactive ion beams (RIBs), where experiments require high solid angle coverage, high efficiency, good position resolution and good neutron-gamma discrimination to overcome low reaction yields and high gamma backgrounds. To address this need, an array of prototype organic liquid-scintillator-based neutron detectors has been developed at Oak Ridge National Laboratory for use in nuclear reaction studies. The Scintillation Array of Bars for Reaction Experiments (SABRE) consists of five 12” long, 2” diameter cylindrical bar detectors filled with custom organic liquid scintillator with individual photomultiplier tube readouts at each end. Use of custom liquid reduces the cost without sacrificing the resolution of the energy (via time of flight) or position determination. In-house purification of the scintillator mixtures resulted in improved pulse shape discrimination and increased light output. Discussion of the liquid scintillator development and the design and commissioning of SABRE will be presented.