Fast Neutron Measurements using Deuterated Liquid Scintillators.

Abstract

This dissertation in experimental nuclear physics describes the construction, design, assembly and tests of a novel 2" X 2" deuterated liquid scintillator, and a series of nuclear reaction experiments using the detector as a fast neutron detector. This detector is unique because of its pulse-shape discrimination capabilities and excellent detection eciency. It is deuterium based and it is liquid. Because of the deuterated benzene (C6D6) inside the liquid scintillator, we are able to determine neutron energies without the use of the time of flight technique. The (d,n) nuclear reactions studied with this detector include the symmetric collision of a 2H beam on a 257 g/cm2 CD2 target, a 2H beam on a 400 g/cm2 enriched 13C target at laboratory energy of E = 9 MeV and a similar 2H beam on a 941 g/cm2 12C target. The experiments were conducted at the joint University of Michigan and University of Notre Dame (UND) Radioactive Nuclear Beam Facility at UND. To verify the detector response to monoenergetic neutrons, additional measurements were done using the 2.45 MeV and 14 MeV neutron generators at the University of Michigan Department of Nuclear Engineering and Radiological Sciences Neutron Science Laboratory. A Monte Carlo simulation code was subsequently modied to simulate the detector response to neutrons. Since very little information is available on detectors using deuterated scintillators, it was important to predict the detector response to various reaction neutron energies to permit use of these detectors in other experiments.