Target Injection and Engagement for Neutron Generation at 1 Hz

Abstract

Target injection is a key technology to realizing inertial fusion energy. Here we present the first demonstration of target injection and neutron generation. We injected more than 600 spherical deuterated polystyrene (C 8 D 8 ) bead targets during 10 minutes at 1 Hz. After the targets fell for a distance of 18 cm, we applied the synchronized laser-diode-pumped ultra-intense laser HAMA and successfully generated neutrons repeatedly. The result is a step toward fusion power and also suggests possible industrial neutron sources.

Review on high repetition rate and mass production of the cryogenic targets for laser IFE

“…The main steps of this production line have been investigated over the period of 1995-2016. They are as follows: mass production of shells [34,[36][37][38][39][40][41] , shell coating with protective layers [42][43][44][45] , fuel filling [30,31,44,46,47] , cryogenic fuel layering [45,46,48,49] , target acceleration and injection [47,[50][51][52][53][54][55][56][57] , flying target tracking and shooting [50,[57][58][59][60][61][62][63] . It is supposed that the first power plants will work with radioactive D-T fuel, which is a major limitation to IFE.…”

Cryogenic Hydrogen Fuel for Controlled Inertial Confinement Fusion (Review of World Results)

“…Исследование работы пневматического инжектора при криогенных температурах и анализ проблемы загрязнения камеры посторонним газом позволят при-нять окончательное решение о применимости пневматического инжектора в реакторах ИТС; -мини-реактор для отработки реакторных технологий. В Японии в рамках создания мини-реактора (программа CANDY) построен неодимовый лазер HAMA с диодной накачкой, c помощью которого впервые экспериментально продемонстрировано синхронное облучение сферических оболочек с частотой 1 Гц и зафиксирован выход термоядерных нейтронов [9,10,132]. Ввод оболочек в камеру осуществлялся при комнатной температуре с помощью гравитационной инжекции.…”

“…На рис. 12, взятом из [9], показан момент двухстороннего облучения инжектированной летящей оболочки светом лазера НАМА.…”

Progress toward a unified kJ-machine CANDY

“…The Laser for Fast Ignition Experiment (LFEX), the most intense laser in the world, heated the preimploded core of a deuterated polystyrene (CD) shell target and increased the core temperature from 0.8 keV to 2 keV. We also present the target injection and engagement results for the first time [3,4]. LFEX, faced to a core as close as possible, directly heated a preimploded core, enhancing D(d, n) 3 He-reacted neutron (DD neutron) yields by a factor of 1000 (5 × 10 8 n/4π sr), the best ever obtained in fast-ignition scheme.…”

“…We also present the target injection and engagement results for the first time [3,4]. LFEX, faced to a core as close as possible, directly heated a preimploded core, enhancing D(d, n) 3 He-reacted neutron (DD neutron) yields by a factor of 1000 (5 × 10 8 n/4π sr), the best ever obtained in fast-ignition scheme. A CD shell was polarily imploded by two counter beams (1.3 ns-515 J) of the GEKKO XII (GXII) green laser.…”