题目: Fast Ignition Realization Experiment with High-Contrast Kilo-Joule Peta-Watt Laser
“LFEX” and Strong External Magnetic Field Shinsuke FUJIOKA
报告人：Professor Fujioka, Institute of Laser Engineering, Osaka University, Japan.
Project manager of Fast Ignition Realization EXperiment (FIREX).
摘要：
Fast Ignition Realization Experiment (FIREX) project that has been curried out at the Institute of Laser Engineering to assess the feasibility of high density core heating with a high-power, short-pulse laser including the construction of the Kilo-Joule, Petawatt class LFEX laser system. Our recent studies identify three scientific challenges to achieve high heating efficiency in the fast ignition (FI) scheme with the current GEKKO and LFEX laser systems: (i) control of relativistic electron beam (REB) energy distribution, (ii) guiding and focusing of REB to a fuel core, and (iii) formation of a high areal-density core. The control of the electron energy distribution has been experimentally confirmed by improving the intensity contrast of the LFEX laser up to >109 and an ultra-high contrast of 1011 with plasma mirrors. After the contrast improvement, 50% of the total REB energy is carried by a low energy component of the REB, which slope temperature is close to the ponderomotive scaling value (~1 MeV). To guide the electron beam, we apply strong external magnetic field to the REB transport region. Guiding of the REB by 0.6 kT field in a planar geometry has already been demonstrated at LULI 2000 laser facility, in a collaborative experiment lead by CELIA-Univ. Bordeaux. Considering more realistic FI scenario, we have performed a similar experiment using the Kilo-Joule LFEX laser to study the effect of guiding and magnetic mirror on the electron beam. A high density core of a laser-imploded 200 µm-diameter solid CD ball was radiographed with picosecond LFEX-produced K-alpha backlighter. Comparisons of the experimental results and integrated simulations using hydrodynamic and electron transport codes suggest that 10% of the efficiency can be achievable with the current GEKKO and LFEX laser system.
简介：
Professor, Institute of Laser Engineering, Osaka University, Japan.
Project manager of Fast Ignition Realization EXperiment (FIREX).
Received Bc. degree from Faculty of Engineering, Osaka University in 1999, Mc. and Dc. degrees from Graduated School of Engineering, Osaka University in 2001 and 2005.
Scientific interests are laser-based nuclear fusion, laser-plasma interactions, atomic physics under extreme conditions such as high intense x-rays and magnetic fields.
时间：2015年12月21日上午9：00
地点：中科院物理研究所M236会议室
联系人：金奎娟 研究员 （Tel：82648099）
邀请人：张喆 研究员 （Tel：82649903）
主办单位：中国科学院光物理重点实验室
