@techreport{oai:nifs-repository.repo.nii.ac.jp:00010044,
 author = {"Nakamura,  Y. and Takeiri,  Y. and Kumazawa,  R. and Osakabe,  M. and Seki,  T. and Peterson,  B. J. and Ida,  K. and Tamura,  N. and Komori,  A. and Morita,  S. and Narihara,  K. and Nagayama,  Y. and Sato,  K. and Tokuzawa,  T. and Noda,  N. and Mutoh,  T. and Shimozuma,  T. and Kawahata,  K. and Funaba,  H. and Goto,  M. and Ikeda,  K. and Inagaki,  S. and Masuzaki,  S. and Miyazawa,  J. and Morisaki,  T. and Muto,  S. and Oka,  Y. and Sakakibara,  S. and Suzuki,  H. and Tanaka,  K. and Watari,  T. and Yamada,  H. and Yokoyama,  M. and Yoshimura,  Y. and Ohyabu,  N. and Sudo,  S. and Matsuoka,  K. and Motojima,  O. and LHD, experimental group"},
 month = {Oct},
 note = {"The superconducting machine LHD has conducted long pulse experiments for four years to achieve long-duration plasmas with high performance. The operational regime was largely extended in the discharge duration and the plasma density. In this paper, the plasma characteristics, in particular, plasma performance and impurity behavior in long pulse discharges are described. Confnement studies show that global energy confinement times are compared with those in short-pulse discharges. Long sustainment of high performance plasma, which is equivalent to the previous achievement in other devices, was demonstrated. Long pulse discharges enabled us to investigate impurity behavior in a long time-scale. Intrinsic metallic impurity accumulation was observed in a narrow density window (2~3 x 10^19 m^-3) only for hydrogen discharges. Finally, impurity accumulation control with an externally induced magnetic island at the plasma edge was demonstrated."},
 title = {Plasma Performance and Impurity Behavior in Long Pulse Discharges on LHD},
 year = {2002}
}