Recent Advances in the Modeling of the Transport of Two-Plasmon--Decay Electrons in the 1-D Hydrodynamic Code \textit{LILAC}

The modeling of the fast-electron transport in the 1-D hydrodynamic code \textit{LILAC} was modified because of the addition of cross-beam-energy-transfer (CBET) in implosion simulations.\footnote{C. J. Randall, J. R. Albritton, and J. J. Thomson, Phys. Fluids \textbf{24}, 1474 (1981).} Using the old fast-electron with source model CBET results in a shift of the peak of the hard x-ray (HXR) production from the end of the laser pulse, as observed in experiments, to earlier in the pulse. This is caused by a drop in the laser intensity of the quarter-critical surface from CBET interaction at lower densities. Data from simulations with the laser plasma simulation environment (LPSE) code\footnote{J. F. Myatt \textit{et al}., ``A Numerical Model for Two-Plasmon--Decay Hot-Electron Production and Mitigation in Direct-Drive Implosions,'' this conference.} will be used to modify the source algorithm in \textit{LILAC}. In addition, the transport model in \textit{LILAC} has been modified to include deviations from the straight-line algorithm and non-specular reflection at the sheath to take into account the scattering from collisions and magnetic fields in the corona. Simulation results will be compared with HXR emissions from both room-temperature plastic and cryogenic target experiments. This material is based upon work supported by the Department of Energy National Nuclear Security Administration under Award Number DE-NA0001944.