|dedx_aps_dpp_05_2.pdf||2006-02-28 11:48:16||Christop Jones|
Stopping in Warm Dense Matter: Theory and Simulation
Author: Christop S Jones
Submitted: 2005-12-21 19:38:44
Co-authors: M.S. Murillo, S. Son
Los Alamos National Laboratory
Los Alamos, NM 87545
Fast ignition via energy deposition through electron or ion stopping has recently emerged as an interesting alternative to conventional inertial confinement fusion. Work at Los Alamos is particularly concerned with ion- rather than electron-based fast ignition, although our theoretical and computational studies are general enough to address both. The theoretical framework for the stopping of charged particles in the warm dense matter regime is still largely incomplete. In this regime, the effects of electron degeneracy, quantum diffraction, and strong coupling between target particles may all contribute, and some cases of interest to heavy ion fast ignition may also involve nonlinear coupling between the projectile and target. Our studies are focused on determining through comparisons between simulation and theory the roles played by these many effects. We compare two-component plasma molecular dynamics simulations with a theory based on the Fermi golden rule in a periodic system to study size effects, including the role of collective behaviors in stopping. We explore the role of mass in simulations of energy deposition as the projectile is varied from electrons to heavy ions. Finally, we will discuss the splitting of deposited energy between ions and electrons, both as observed in simulation and predicted by theory.