Proof-of-principle measurement of beta-delayed neutron precursor 89Br using VANDLE
ORAL
Abstract
The Versatile Array of Neutron Detectors at Low Energy (VANDLE) uses the time of flight technique to measure the energy of neutrons from various nuclear processes. Beta delayed neutrons from fission fragments typically have an energy below 1 MeV, making measurements of their energy challenging. This has led to the use of a reliable off-the-shelf digital electronics system to instrument VANDLE. However, the timing resolution and neutron-energy threshold of the system required investigation. Timing resolutions better than 1 ns have been obtained. The digital system can be operated with low thresholds to obtain high detection efficiency for low energy neutrons (E$>$150 keV). A proof-of-principle experiment using $^{89}$Br was conducted at the Holifield Radioactive Ion Beam Facility (HRIBF) at Oak Ridge National Laboratory (ORNL). $^{89}$Br is produced in proton induced fission of $^{238}$U and was chosen because its neutron energy spectrum has been measured by G. Ewan et. al.(Z. Phys. A. 318, 309-314, (1984)).
*This research was sponsored by the National Nuclear Security Administration under the Stewardship Science Academic Alliances program through DOE Co- operative Agreement No. DE-FG52-08NA28552.
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