@article{oai:nifs-repository.repo.nii.ac.jp:00010753,
 author = {YOSHIMURA,  Yasuo and KASAHARA,  Hiroshi and TOKITANI,  Masayuki and SAKAMOTO,  Ryuichi and Ueda,  Y. and ITO,  Satoshi and OKADA,  Koji and KUBO,  Shin and SHIMOZUMA,  Takashi and IGAMI,  Hiroe and TAKAHASHI,  Hiromi and TSUJIMIRA, Toru and TSUJIMURA, Toru Ii and MAKINO,  Ryohei and KOBAYASHI,  Sakuji and MIZUNO,  Yoshinori and AKIYAMA,  Tsuyoshi and ASHIKAWA,  Naoko and MASUZAKI,  Suguru and MOTOJIMA,  Gen and SHOJI,  Mamoru and SUZUKI,  Chihiro and TANAKA,  Hirohiko and TANAKA,  Kenji and TOKUZAWA,  Tokihiko and TSUCHIYA,  Hayato and YAMADA,  Ichihiro and GOTO, Y. and YAMADA, Hiroshi and MUTOH,  Takashi and KOMORI,  Akio and TAKEIRI,  Yasuhiko and LHD, Experiment Group},
 issue = {4},
 journal = {Nuclear Fusion},
 month = {Mar},
 note = {0000-0001-6744-1829, Using ion cyclotron heating and electron cyclotron heating (ECH), or solo ECH, trials of steady state plasma sustainment have been conducted in the superconducting helical/stellarator, large helical device (LHD) (Ida K et al 2015 Nucl. Fusion 55 104018). In recent years, the ECH system has been upgraded by applying newly developed 77 and 154 GHz gyrotrons. A new gas fueling system applied to the steady state operations in the LHD realized precise feedback control of the line average electron density even when the wall condition varied during long pulse discharges. Owing to these improvements in the ECH and the gas fueling systems, a stable 39 min discharge with a line average electron density ne_ave of 1.1  ×  1019 m−3, a central electron temperature Te0 of over 2.5 keV, and a central ion temperature Ti0 of 1.0 keV was successfully performed with ~350 kW EC-waves. The parameters are much improved from the previous 65 min discharge with ne_ave of 0.15  ×  1019 m−3 and Te0 of 1.7 keV, and the 30 min discharge with ne_ave of 0.7  ×  1019 m−3 and Te0 of 1.7 keV.},
 title = {Progress of long pulse discharges by ECH in LHD},
 volume = {56},
 year = {2016}
}