Influence of laser field on Coulomb logarithm with MD simulations

Coulomb logarithm, ($\ln(\Lambda)$), is involved in several important quantities of high energy density plasmas such as inverse bremsstrahlung absorption, electron-ion temperature relaxation frequency, electron conduction and more. Molecular-dynamic (MD) simulations of Plasmas of Ions and electrons in COulomb interaction have been carried out with our code PIeCO to measure numerically $\ln(\Lambda)[n_e, T_e]$ out of the velocity damping of electrons through ions. PIeCO reproduced results of MD simulations by Dimonte and Daligault [1] and theoretical results by BPS [2]. The work presented in this talk will focus on PIeCO simulations of the same type of plasmas subjected, in addition, to oscillating electric fields (to mimic a laser field with $\lambda$=351 nm and intensities ranging from I=$10^{11}$ to $10^{15}$ W/cm$^2$). The results of these MD simulations allowed to grasp the non-trivial variation of $\ln(\Lambda)$ with respect to $I$ and $\lambda$ (in addition to $n_e$ and $T_e$). A best fit of $\ln(\Lambda)[n_e, T_e, I, \lambda]$ involving all 4 parameters will be presented. \\ \\1. G. Dimonte and J. Daligault, PRL {\bf 101}, 135001 (2008)\\ 2. L.S. Brown et al., Phys. Reports {\bf 410}, 237 (2005)