CR-39 Neutron Sensitivity Study for Improved ODIN Neutron Response Function Analysis*

The one-dimensional imager of neutrons (ODIN) at the Sandia Z facility was designed to determine the size, shape, and location of the neutron producing region in Sandia’s baseline ICF concept, namely magnetized liner inertial fusion (MagLIF). Modeling efforts with subsequent IBL experiments continue to advance the neutron imager using an HDPE converter and CR-39 plastic detector. Sandia’s Ion Beam Laboratory (IBL) was used to experimentally determine CR-39 DD and DT neutron sensitivity (with and without an HDPE (n,p) converter foil), edge spread function, and resolution. The HDPE converter will produce roughly four times as many tracks as the unfiltered CR-39, increasing the CR-39 sensitivity of 1e-4 tracks per neutron. This will produce an edge spread function that can be analyzed with current MCNP6.1 point spread model. Finally, modeling efforts of proton recoil (DD and DT neutrons entering CR-39 with and without HDPE converter) will be shown to further understand the resolution of the CR-39 detector.