Monte Carlo calculation of high energy neutron responses for improved Andersson-Braun rem meters

In an improved Andersson-Braun (A-B) rem meter, Pb(n, xn) reactions at high neutron energies increase rem meter sensitivity when lead replaces a small part of the neutron-moderating material, polyethylene. Monte Carlo calculations were carried out using the Los Alamos High-Energy Transport code (LAHET) and Monte Carlo Neutron Transport (MCNP) code for both standard and lead-modified A-B rem meters with monoenergetic neutrons (up to 2.1 GeV). Experiments for medium and high energy tests (23.6 MeV-2.1 GeV at nine energy values) verified the results of theoretical calculations of response enhancement. Thus, Monte Carlo calculations that use the LAHET and MCNP codes prove to be powerful tools to simulate new nuetron detectors. (author)