@article{oai:nifs-repository.repo.nii.ac.jp:00000137,
 author = {"Yamada,  H. and Sakamoto,  R. and Miyazawa,  J. and Kobayashi,  M. and Morisaki,  T. and Masuzaki,  S. and Ohdachi,  S. and Goto,  M. and Ida,  K. and Sakakibara,  S. and Tanaka,  K. and Ashikawa,  N. and Itoh,  K. and Morita,  S. and Nagayama,  Y. and Narushima,  Y. and Peterson,  B.J. and Shoji,  M. and Suzuki,  C. and Suzuki,  Y. and Tokuzawa,  T. and Watanabe,  K.Y. and Yamada,  I. and Yokoyama,  M. and Yoshimura,  S. and Yoshinuma,  M. and Imagawa,  S. and Kaneko,  O. and Kawahata,  K. and Mutoh,  T. and Ohyabu,  N. and Komori,  A. and Motojima,  O."},
 journal = {Plasma Physics and Controlled Fusion},
 month = {Nov},
 note = {"A high density regime with an internal diffusion barrier (IDB) has been extended to the helical divertor (HD) configuration in the Large Helical Device (LHD). Avoidance of the local enhancement of neutral pressure is necessary to enable IDB formation, which is consistent with earlier works by using the Local Island Divertor (LID) with efficient active pumping. The central pressure reached 1.3 times atmospheric pressure, where ne(0) = 6 × 1020 m?3 and Te(0) = 660 eV. The plasmas with an IDB are located in the plateau collisionality regime. The significant impurity effect has not been observed throughout the discharges in spite of the existence of a negative radial electric field. A central pressure limiting event is observed in the plasmas with an IDB using the HD. During this event which is referred to as the core density collapse (CDC), particles are flushed out from the core on the time scale of a few hundreds of microseconds. The suppression of the Shafranov shift by vertical elongation (κ) is effective to mitigate CDC. At κ = 1.2, the central β value is increased up to 6.6% at 1 T."},
 title = {Characterization and operational regime of high density plasmas with internal diffusion barrier observed in the Large Helical Device},
 volume = {Vol.49},
 year = {2007}
}