@techreport{oai:nifs-repository.repo.nii.ac.jp:00010436,
 author = {Yamada,  H. and Watanabe,  K. Y. and Yamazaki,  K. and Murakami,  S. and Sakakibara,  S. and Narihara,  K. and Tanaka,  K. and Osakabe,  M. and Ida,  K. and Rewoldt,  G. and Ashikawa,  N. and deVaries,  P. and Emoto,  M. and Funaba,  H. and Goto,  M. and Idei,  H. and Ikeda,  K. and Inagaki,  S. and Inoue,  N. and Isobe,  M. and Kado,  S. and Kaneko,  O. and Kawahata,  K. and Khlopenkov,  K. and Komori,  A. and Kubo,  S. and Kumazawa,  R. and Masuzaki,  S. and Minami,  T. and Miyazawa,  J. and Morisaki,  T. and Morita,  S. and Muto,  S. and Mutoh,  T. and Nagayama,  Y. and Nakajima,  N. and Nakamura,  Y. and Nakanishi,  H. and Nishimura,  K. and Noda,  N. and Notake,  T. and Kobuchi,  T. and Liang,  Y. and Ohdachi,  S. and Ohyabu,  N. and Oka,  Y. and Ozaki,  T. and Pavlichenko,  R. O. and Peterson,  B. J. and Sagara,  A. and Saito,  K. and Sakamoto,  R. and Sasao,  H. and Sasao,  M. and Sato,  K. and Sato,  M. and Seki,  T. and Shimozuma,  T. and Shoji,  M. and Sugama,  H. and Suzuki,  H. and Takechi,  M. and Takeiri,  Y. and Tamura,  N. and Toi,  K. and Tokuzawa,  T. and Torii,  Y. and Tsumori,  K. and Yamada,  I. and Yamaguchi,  S. and Yamamoto,  S. and Yokoyama,  M. and Yoshimura,  Y. and Watari,  T. and Itoh,  K. and Matsuoka,  K. and Ohkubo,  K. and Ohtake,  I. and Satoh,  S. and Satow,  T. and Sudo,  S. and Tanahashi,  S. and Uda,  T. and Hamada,  Y. and Motojima,  O. and Fujiwara,  M.},
 month = {Sep},
 note = {The energy confinement and thermal transport characteristics of net-current free plasmas in the much smaller gyro-radii and collisionality regimes than before have been investigated in the Large Helical Device (LHD). The inward shifted configuration that is superior from the theoretical aspect of neoclassical transport has revealed a systematic confinement improvement on a standard configuration. The improvement of energy confinement times on the international stellarator scaling 95 occurs with a factor of 1.6 pm 0.2 for an inward shifted configuration. This enhancement is primarily due to the broad temperature profile with a high edge value. A simple dimensional analysis involving LHD and other medium sized heliotrons yields strongly gyro-Bohm dependence (tau_E Omega propto rho^ast-3.8) of energy confinement times. It should be noted that this result is attributed to comprehensive treatment of LHD for systematic confinement enhancement and that the medium sized heliotrons have narrow temperature profiles. The core stored energy still indicates the dependence of tau_E omega propto rho^ast-2.6 when data only from LHD is processed. The local heat transport analysis of dimensionally similar discharges except for rho^ast suggests that the heat conduction coefficient lies between Bohm and gyro-Bohm in the core and changes towards strong gyro-Bohm in the peripheral region. Since the inward shifted configuration has a geometrical feature suppressing the neoclassical transport, confinement improvement can be maintained in the collisionless regime where the ripple transport is important. The stiffness of the pressure profile coincides with enhanced transport in the peaked density profile obtained by pellet injection.},
 title = {Energy Confinement and Thermal Transport Characteristics of Net-Current Free Plasmas in Large Helical Device},
 year = {2000}
}