Direct fast heating efficiency of a counter-imploded core plasma employing a laser for fast ignition experiments (LFEX)

Nuclear Fushion

article

Yoneyoshi Kitagawa¹  Yoshitaka Mori¹  Katsuhiro Ishii¹  Ryohei Hanayama¹  Shinichiro Okihara¹  Yasunobu Arikawa²  Yuki Abe²  Eisuke Miura³  Tetsuo Ozaki⁴  Osamu Komeda⁵  Hiroyuki Suto⁵  Yusuke Umetani⁵  Atsushi Sunahra⁶  Tomoyuki Johzaki⁷  Hitoshi Sakagami⁴  Akifumi Iwamoto⁴  Yasuhiko Sentoku²  Nozomi Nakajima²  Shohei Sakata²  Kazuki Matsuo²  Reza S. Mirfayzi²  Junji Kawanaka²  Shinsuke Fujiokua²  Koji Tsubakimoto²  Keisuke Shigemori²  Kohei Yamanoi²  Akifumi Yogo²  Ayami Nakao²  Masatada Asano²  Hiroyuki Shiraga²  Tomoyoshi Motohiro⁸  Tatsumi Hioki⁸  Hirozumi Azuma⁹ 

[1] The Graduate School for the Creation of New Photonics Industries;Osaka Univ.;AIST;NIFS;Advanced Material Engineering Division;Purdue Univ.;Hiroshima Univ. Eng.;Institute of Materials Innovation;Aichi SRC

关键词: counter implosion;    fast ignition;    direct heating;    heating efficiency;   

DOI  :  10.1088/1741-4326/ac7966

来源: Institute of Physics Publishing Ltd.

【 摘 要 】

Fast heating efficiency when a pre-imploded core is directly heated with an ultraintense laser (heating laser) was investigated. 'Direct heating' means that a heating laser hits a pre-imploded core without applying either a laser guiding cone or an external field. The efficiency,η , is defined as the increase in the internal core energy divided by the energy of the heating laser. Six beams (output of 1.6 kJ) from the GEKKO XII (GXII) green laser system at the Institute of Laser Engineering (ILE), Osaka University were applied to implode a spherical deuterated polystyrene (CD) shell target to form a dense core. The DD-reacted protons and the core x-ray emissions showed a core density of 2.8 ± 0.7 g cm⁻³, or 2.6 times the solid density. Furthermore, DD-reacted thermal neutrons were utilized to estimate the core temperature between 600 and 750 eV. Thereafter, the core was directly heated by a laser for fast-ignition experiments (LFEX, an extremely energetic ultrashort pulse laser) at ILE with its axis lying along or perpendicular to the GXII bundle axis, respectively. The former and latter laser configurations were termed 'axial' and 'transverse modes', respectively. Theηwas estimated from three independent methods: (1) the core x-ray emission, (2) the thermal neutron yield, and (3) the runaway hot electron spectra. For the axial mode, 0.8%

【 授权许可】

Unknown