@techreport{oai:nifs-repository.repo.nii.ac.jp:00010123,
 author = {"Okamura,  S. and Matsuoka,  K. and Akiyama,  R. and Darrow,  D.S. and Ejiri,  A. and Fujisawa,  A. and Fujiwara,  M. and Goto,  M. and Ida,  K. and Iguchi,  H. and Inoue,  N. and Isobe,  M. and Itoh,  K. and Kado,  S. and Khlopenkov,  K. and Kondo,  T. and Kubo,  S. and Lazaros,  A. and Lee,  S. and Matsunaga,  G. and Minami,  T. and Morita,  S. and Murakami,  S. and Nakajima,  N. and Nikai,  N. and Nishimura,  S. and Nomura,  I. and Ohdachi,  S. and Ohkuni,  K. and Osakabe,  M. and Pavlichenko,  R. and Peterson,  B. and Sakamoto,  R. and Sanuki,  H. and Sasao,  M. and Shimizu,  A. and Shirai,  Y. and Sudo,  S. and Takagi,  S. and Takahashi,  C. and Takayama,  S. and Takechi,  M. and Tanaka,  K. and Toi,  K. and Yamazaki,  K. and Yoshimura,  Y. and Watari,  T."},
 month = {Oct},
 note = {"The configuration parameter of the plasma position relative to the center of helical coil winding is very effective one to control the MHD stability and the trapped particle confinement in Heliotron/Torsatron systems. But these two characteristics are contradictory in this parameter to each other. Inward shifted configuration is favorable for the drift-orbit-optimization but it is predicted unstable with the Mercier criterion. Various physics problems, such as an electric field structure, plasma rotation, MHD phenomena, have been studied in CHS with a compromising intermediate position. With this standard configuration, CHS has supplied experimental results for understanding general toroidal confinement physics and low-aspect-ratio helical systems. In the recent experiments, it was found that the wide range of inward shifted configurations gives stable plasma discharges without any restriction to the special pressure profile. Such enhanced range of operation made it possible to study experimentally the drift-orbit-optimized configuration in the Heliotron/Torsatron systems. The effect of configuration improvement was studied with plasmas in a low collisionality regime."},
 title = {Confinement Physics Study in a Small Low-Aspect-Ratio Helical Device CHS},
 year = {1998}
}