1H(n,el) as a Cross Section Reference in a White Source Neutron Beam With the fissionTPC
Abstract
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 U(n,f) and U(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.
Keywords
Cite
@article{arxiv.1904.10558,
title = {1H(n,el) as a Cross Section Reference in a White Source Neutron Beam With the fissionTPC},
author = {N. I. Walsh and J. T. Barker and N. S. Bowden and K. J. Brewster and R. J. Casperson and T. Classen and N. Fotiadis and U. Greife and E. Guardincerri and C. Hagmann and M. Heffner and D. Hensle and C. R. Hicks and D. Higgins and L. D. Isenhower and A. Kemnitz and K. J. Kiesling and J. King and J. L. Klay and J. Latta and W. Loveland and J. A. Magee and M. P. Mendenhall and M. Monterial and S. Mosby and G. Oman and S. Sangiorgio and B. Seilhan and L. Snyder and C. L. Towell and R. S. Towell and T. R. Towell and K. T. Schmitt and S. Watson and L. Yao and W. Younes},
journal= {arXiv preprint arXiv:1904.10558},
year = {2019}
}