@article{oai:repo.qst.go.jp:00048925,
 author = {高瀬, 雄一 and Ejiri, A. and Fujita, T. and Fukumoto, N. and Fukuyama, A. and Hanada K. and Idei, H. and Nagata, M. and Ono, Y. and Tanaka, H. and M.Uchida and Horiuchi, R. and 鎌田, 裕 and Kasahara, H. and Masuzaki, S. and Nagayama, Y. and Oishi, T. and Saito, K. and Takeiri, Y. and 鎌田 裕},
 issue = {10},
 journal = {Nuclear Fusion},
 month = {May},
 note = {Nationally coordinated research on spherical tokamak is being conducted in Japan. Recent achievements include: (i) plasma current start-up and ramp-up without the use of the central solenoid by RF waves (in electron cyclotron and lower hybrid frequency ranges), (ii) plasma current start-up by AC Ohmic operation and by coaxial helicity injection, (iii) development of an advanced fuelling technique by compact toroid injection, (iv) ultra-long-pulse operation
and particle control using a high temperature metal wall, (v) access to the ultra-high-β regime by high-power reconnection heating, and (vi) improvement of spherical tokamak plasma stability by externally applied helical field.},
 title = {Overview of spherical tokamak research in Japan},
 volume = {57},
 year = {2018}
}