Measuring fuel ρR for inertial fusion experiments using neutron elastic-scattering reactions

Neutron elastic‐scattering reactions are examined by computer simulation and found to be potentially useful as a diagnostic for fuel ρR (density‐radius product). We show how previously anticipated uncertainties can be removed by correlating the distortion of the scattered‐ion distribution with energy loss of DD protons for low ρR and with D‐He3 protons for large ρR. This diagnostic could be used to directly measure ρR of the fuel without special target preparation for target ρR≲0.2 g/cm2.