開催報告：日米高エネルギー密度セミナー（Speaker: Dr. Annie Kritcher, LLNL）

第２回日米高エネルギー密度セミナーが５月１７日に開催されました。
ローレンス・リバモア国立研究所の Annie Kritcher博士に「最初に利得1を超えたNIF点火実験のデザイン」のタイトルで講演いただきました。
昨年１２月のNIFの実験で、どのような改善により3MJの核融合エネルギーが達成されたか、デザインの観点から話をお聞きしました。

–Speaker: —
Dr. Annie Kritcher
Lawrence Livermore National Laboratory

–Title–
Design of the first fusion laboratory experiment to achieve target gain > 1

–Abstract: —
The inertial fusion community have been working towards ignition for decades, since the idea of inertial confinement fusion (ICF) was first proposed by Nuckolls, et al., in 1972. On August 8, 2021 and Dec 5th 2022, the Lawson criterion for ignition was met and more fusion energy was created than laser energy incident on the target at the National Ignition Facility (NIF) in Northern California. The first experiment produced a fusion yield of 1.35 MJ from 1.9 MJ of laser energy and appears to have crossed the tipping-point of thermodynamic instability according to several ignition metrics. Building on this result, improvements were made to increase the fusion energy output to >3MJ from 2.05 MJ of laser energy on target, resulting in target gain exceeding unity for the first time in the laboratory. This result is important in that it proves that there is nothing fundamentally limiting controlled fusion energy gain in the laboratory. The presentation will detail the changes made to achieve this result.