Speaker
Description
Improved inelastic neutron scattering and neutron-induced gamma-ray production data are needed for the next generation of nuclear technologies, from advanced reactors to space exploration, shielding applications, and detection platforms based on prompt neutron interrogation analysis.
The Gamma Energy Neutron Energy Spectrometer for Inelastic Scattering (GENESIS), located at the 88-Inch Cyclotron at Lawrence Berkeley National Lab, is the first-ever array of neutron detectors coupled to high-purity germanium detectors designed to address these nuclear data needs.
In addition to single particle measurement of quantities like double-differential gamma-ray production, GENESIS can more accurately measure secondary neutron energy-angle distributions by tagging on coincident, characteristic gamma-rays.
Experiments with a $99.98\%$-enriched $^{56}$Fe target were performed at GENESIS. These experiments used a broad-energy collimated, time-resolved incident neutron spectrum from 14 MeV Thick-Target Deutron Breakup (TTDB), measured \textit{in situ} with a newly developed, kinematic-based neutron spectrometer. Frame-overlap between neutrons of temporally-sequential deuteron beam pulses created a degeneracy in the determination of neutron energy from time-of-flight.
This issue motivated the development of a forward modeling approach that naturally includes contributions from different neutron energies in the analysis and interpretation of GENESIS data.
This presentation will describe the design of the forward model, including the development of a nuclear data driven event generator. Preliminary results from the $^{56}$Fe experiments will also be presented, including double-differential gamma ray production cross sections, and gamma-ray tagged scattered neutron angular distributions.