Railgun system using a laser‐induced plasma armature

Development of an electromagnetic railgun system that utilizes a laser‐induced plasma armature formation has been conducted to investigate the application of the railgun system for high‐speed pellet injection into fusion plasmas. Using the laser‐induced plasma formation technique, the required breakdown voltage was reduced by one‐tenth compared with that for the spark‐discharged plasma. The railgun system successfully accelerated the laser‐induced plasma armature by an electromagnetic force that accelerated the pellet. The highest velocity of the solid hydrogen pellets, obtained so far, was 2.6 km/sec using a 2m‐long railgun.