Evaluating the Residual Kinetic Energy in Direct-Drive Cryogenic Implosions on OMEGA*

Efficient conversion of the shell kinetic energy to the hot-spot thermal energy is an essential requirement in inertial confinement fusion implosions. The spectral moments of the neutron energy distribution emitted from a fusing deuterium–tritium (DT) plasma is used to infer the yield, mean energy, and neutron averaged ion temperature of the implosion. Flows in the reacting plasma will have a different effect on the DD and DT neutron distribution, resulting in a disagreement between the inferred ion temperatures from the two separate reactions. Enhanced broadening of the peak distributions of the different reactants provides a measure of the residual kinetic energy in the fusion plasma.[1] Evaluation of residual kinetic energy from direct-drive cryogenic DT implosions on OMEGA is presented.  

[1] T. J. Murphy, Phys. Plasmas 21, 072701 (2014).