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22–27 Oct 2018
Mahatma Mandir Conference Centre
Asia/Kolkata timezone
CONFERENCE MATERIAL NOW AVAILABLE!

Production of keV-Temperature Plasma Core with Magnetized Fast Isochoric Heating

24 Oct 2018, 08:50
20m
Mahatma Mandir Conference Centre

Mahatma Mandir Conference Centre

Gandhinagar (nearest Airport: Ahmedabad), India
Oral IFE - Inertial Fusion Experiments and Theory IFE/1 Inertial Fusion Experiments & Theory

Speaker

Prof. Shinsuke Fujioka (Institute of Laser Engineering, Osaka University)

Description

The quest for the inertial confinement fusion (ICF) ignition is a grand challenge, as exemplified by extraordinary large laser facilities like National Ignition Facility (NIF) [J. Lindl et al., Phys. Plasmas 11, 339 (2004), J. Lindl et al., Phys. Plasmas 21, 020501 (2014)]. Although scientific break-even, the energy released by fusion reaction exceeds the energy contains in the compressed fusion fuel, was achieved on NIF [O. A. Hurricane et al., Nature 506, 343 (2014)], the pathway to the ignition is still unclear. Fast isochoric heating, also known as fast ignition, of a pre-compressed fuel core with a high-intensity laser is an attractive and alternative approach to the ICF ignition [M. Tabak et al., Phys. Plasmas 1, 1637 (1994)] that avoids the ignition quench caused by the hot spark mixing with the cold fuel, which is the crucial problem of the currently pursued ignition scheme. High-intensity laser-plasma interactions efficiently produce relativistic electron beams (REB). However, only a small portion of the REB collides with the core because of its large divergence. Here we have demonstrated enhanced laser-to-core coupling with a magnetized method to confine the REB in a narrow transport region resulting in efficient isochoric heating. The method employs a laser-produced kilo-tesla-level magnetic field [S. Fujioka et al., Sci. Rep., 3, 1170 (2013)] that is applied to the transport region from the REB generation point to the core which results in guiding the REB along the magnetic field lines. We have created successfully a 1.6 ± 0.2 keV-temperature plasma core having 1 Gbar of energy density by using the MFI scheme with 7.7 ± 1.3% of an efficient laser-to-core energy coupling [S. Sakata et al., ArXiv 172.06029 (2017)]. We should emphasize that our result can be explained by a simple model coupled with the comprehensive plasma diagnostics, while several ICF experiments relay heavily on computer simulations due to difficulties of diagnosing micro-scale phenomena occurred in the small and complex plasma. The simplicity may secure scalability of this scheme to the ignition. 15% of the laser-to-core coupling is achievable for an ignition-scale high area density core (0.3 - 0.5 g/cm2) according to the model. The ignition target based on the MFI scheme is being designed by using multi-scale and multi-dimensional simulations.
Country or International Organization Japan
Paper Number IFE/1-2

Primary author

Prof. Shinsuke Fujioka (Institute of Laser Engineering, Osaka University)

Co-authors

Dr Akifumi Yogo (Institute of Laser Engineering, Osasa University) Mr Akira Yao (Institute of Laser Engineering, Osaka University) Dr Alessio Morace (Institute of Laser Engineering, Osaka University) Dr Atsushi Sunahara (Institute for Laser Technology) Dr Hideo Nagatomo (Osaka University) Mr Hidetaka Kishimoto (Institute of Laser Engineering, Osaka University) Prof. Hiroaki Nishimura (Institute of Laser Engineering, Osaka University) Mr Hiroki Morita (Institute of Laser Engineering, Osaka University) Prof. Hiroshi AZECHI (Institute of Laser Engineering, Osaka University) Dr Hiroshi Sawada (Department of Physics, University of Nevada, Reno) Prof. Hiroyuki Shiraga (Institute of Laser Engineering, Osaka University) Prof. Hitoshi Sakagami (National Institute for Fusion Sciences) Dr Joao Jorge Santos (CELIA, University of Bordeaux) Prof. Junji Kawanaka (Institute of Laser Engineering, Osaka University) Mr King Fai Farley Law (Institute of Laser Engineering, Osaka University) Dr Kohei Yamanoi (Institute of Laser Engineering, Osaka University) Dr Koji Tsubakimoto (Institute of Laser Engineering, Osaka University) Prof. Kunioki Mima (The Graduate School for the Creation of New Photon Industries) Dr Masayasu Hata (Institute of Laser Engineering, Osaka University) Dr Mathieu Bailly-Grandvaux (CELIA, University of Bordeaux) Prof. Mitsuo Nakai (Institute of Laser Engineering, Osaka University) Dr Nakata Yoshiki (Institute of Laser Engineering, Osaka University) Prof. Naofumi Ohnishi (Department of Aerospace Engineering, Tohoku University) Dr Natsumi Iwata (Institute of Laser Engineering, Osaka University) Prof. Noriaki Miyanaga (Institute of Laser Engineering, Osaka University) Prof. Ryosuke Kodama (Institute of Laser Engineering, Osaka University) Dr Sadaoki Kojima (Institute of Laser Engineering, Osaka University) Mr Seungho Lee (Institute of Laser Engineering, Osaka University) Dr Shigeki Tokita (Institute of Laser Engineering, Osaka University) Dr Shohei Sakata (Institute of Laser Engineering, Osaka University) Dr TOMOYUKI JOHZAKI (Graduate School of Engineering, Hiroshima University) Prof. Takahisa Jitsuno (Institute of Laser Engineering, Osaka University) Dr Takashi Shiroto (Department of Aerospace Engineering, Tohoku University) Prof. Takayoshi Norimatsu (Institute of Laser Engineering, Osaka University) Dr Tetsuo Ozaki (National Institute for Fusion Science) Prof. Yasuhiko Sentoku (Institute of Laser Engineering, Osaka University) Dr Yasunobu Arikawa (Insituteof Laser Engineering Osaka University) Dr Yuki Abe (Institute of Laser Engineering, Osaka University)

Presentation materials