Studies of neutron–γγ pulse shape discrimination in EJ-309 liquid scintillator using charge integration method

Pulse shape discrimination capability based on the charge integration has been investigated for liquid scintillator EJ-309. The effectiveness of neutron–γγ discrimination in 4-in. diameter and 3-in. thick EJ-309 cells coupled with 3-in. photomultiplier tubes has been carefully studied in the laboratory environment and compared to the commonly used EJ-301 liquid scintillator formulation. Influences of distortions in pulse shape caused by 13.7-m long cables necessary for some remote operations have been examined. The parameter space for an effective neutron–γγ discrimination for these assays, such as position and width of a gate used for integration of the delayed light, has been explored.