Evaluation of a digital data acquisition system for an NE213 spectrometer and optimization of n-y discrimination
L. Giacomelli, M. Reginatto, K. Tittelmeier, A. Zimbal
A compact NE213 liquid scintillation neutron spectrometer with a new digital data acquisition (DAQ) system is in operation at the Physikalisch-Technische Bundesanstalt (PTB). With the DAQ system, developed by ENEA Frascati, neutron spectrometry with high count rates is possible, roughly an order of magnitude higher than what is achievable with an analogue acquisition system. The digital acquisition system has two modes of operation: The acquisition mode, which records events produced in NE213 as digitized pulse shapes, and the processing mode, which permits off-line analysis to produce pulse height spectra and perform neutron and gamma discrimination based on the two gate method. To validate the two modes of operation of the DAQ system, an independent method of analysis was developed and measurements of 14-MeV neutrons made at the PTB accelerator facility were analyzed and compared.