2019/04/23 by Nicholas Ian Walsh, N. I. Walsh, J. T. Barker +78
Engineering · Physics and Astronomy · #Beam (structure) #Cross section (physics) #FOS: Physical sciences #Fission #Instrumentation and Detectors (physics.ins-det) #Neutron #Neutron cross section #Neutron detection #Neutron radiation #Neutron scattering #Neutron source #Nuclear Experiment (nucl-ex) #Nuclear Physics and Applications #Nuclear physics #Nuclear reactor physics and engineering #Optics #Physics #Proton #Radiation Detection and Scintillator Technologies #Spallation Neutron Source #nucl-ex #physics.ins-det
paper · pdf · doi:10.48550/arxiv.1904.10558
published in arXiv (Cornell University) (Cornell University)
arxiv created 2019/04/23 · openalex publication_date 2019/04/23 · arxiv updated 2019/04/25 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We provide a quantitative description of a method to measure neutron-induced fission cross sections in ratio to elastic hydrogen scattering in a white-source neutron beam with the fission Time Projection Chamber. This detector has measured precision fission cross section ratios using actinide references such as 235U(n,f) and 238U(n,f). However, by employing a more precise reference such as the H(n,el) cross section there is the potential to further reduce the evaluation uncertainties of the measured cross sections. In principle the fissionTPC could provide a unique measurement by simultaneously measuring both fission fragments and proton recoils over a large solid angle. We investigate one method with a hydrogenous gas target and with the neutron energy determined by the proton recoil kinematics. This method enables the measurement to be performed in a white-source neutron beam and with the current configuration of the fissionTPC. We show that while such a measurement is feasible in the energy range of 0.5 MeV to ∼10 MeV, uncertainties on the proton detection efficiency and the neutron energy resolution do not allow us to preform a fission ratio measurement to the desired precision. Utilizing either a direct measurement of the neutron time-of-flight for the recoil proton or a mono-energetic neutron source or some combination of both would provide a path to a sub-percent precision measurement.