Comparison of neutron scintillation detectors with a 3He proportional counter for the Spallation Neutron Source (SNS)

The performance of scintillation detectors with the advanced scintillator material ⁶Li ¹⁵⁸Gd (¹¹BO₃)₃ was compared with conventional ³He proportional counters at the IPNS spallation source at the Argonne National Laboratory, Argonne, IL. The complex neutron and gamma flux was measured with both detector types simultaneously in time-of-flight mode. Initial experiments demonstrated that both detectors have a sensitivity of about 60% for thermal neutrons. In addition, both detectors exhibited the same low gamma sensitivity.