開催報告:9月6日 日米高エネルギー密度科学セミナー(Speaker: Dr. Liam Stanto, San Jose State University)
日米高エネルギー密度科学セミナーが9月6日 9:00am(日本時間)からオンラインにて開催されました。
講 師: Liam Stanto博士(San Jose State University)
タイトル: 高エネルギー密度プラズマ中の荷電粒子輸送モデル
縮退したような超高密度プラズマ中の輸送係数を計算するために必要な理論モデルについてお話頂きました。
–Speaker–
Dr. Liam Stanton
San Jose State University
–Title–
Charged Particle Transport in Hydrodynamic Models for High Energy-Density Plasmas”
–Abstract–
Transport processes are important to quantify accurately in the hydrodynamic description of plasmas, where these processes are typically captured through transport coefficients that relate the flux of one quantity in terms of the gradient in another. This talk will explore the extent to which simple screening models for particle interactions can capture the transport processes of non-ideal plasmas, such as the dense plasmas found in inertial confinement fusion (ICF) experiments. We have developed a simplified effective potential approach that borrows from both the Boltzmann and Lenard-Balescu frameworks that yields accurate and computationally efficient fits for all of the relevant cross-sections and collision integrals needed to construct transport coefficients. Our results, which span the parameter regimes relevant to ICF, have been validated with molecular dynamics (MD) simulations for self-diffusion, inter-diffusion, and viscosity, with promising comparisons to experiments as well. MD simulations have also been used to examine the underlying assumptions of this effective Boltzmann approach through a categorization of behaviors of the velocity autocorrelation function. While this model was originally intended for ionic transport, the model can be applied to transport dominated by electronic interactions as well, such as thermal and electrical conductivity. Finally, the model can be extended to include dynamic screening effects for velocity-resolved transport processes like stopping power.