7Li(p,n) NUCLEAR DATA LIBRARY FOR INCIDENT PROTON ENERGIES TO 150 MEV

Researchers at Los Alamos National Laboratory are considering the possibility of using the Low Energy Demonstration Accelerator, constructed at Los Alamos Neutron Science Center for the Accelerator Production of Tritium Project, as a neutron source. Evaluated nu- clear data are needed for the p+7Li reaction, to predict neutron production from thin and thick lithium tar- gets. In this paper we describe evaluation methods that make use of experimental data, and nuclear model cal- culations, to develop an ENDF-formatted data library for incident protons with energies up to 150 MeV. The important 7Li(p,n0) and 7Li(p,n1) reactions are eval- uated from the experimental data, with their angular distributions represented using Lengendre polynomial expansions. The decay of the remaining reaction flux is estimated from GNASH nuclear model calculations. This leads to the emission of lower-energy neutrons and other charged particles and gamma-rays from preequi- librium and compound nucleus decay processes. The evaluated ENDF-data are described in detail, and illustrated in numerous figures. We also illustrate the use of these data in a representative application by a radiation transport simulation with the code MCNPX.