@techreport{oai:nifs-repository.repo.nii.ac.jp:00009593, author = {"Hamada, Y. and Nishizawa, A. and Kawasumi, Y. and Fujisawa, A. and Narihara, K. and Ida, K. and Ejiri, A. and Ohdachi, S. and Kawahata, K. and Toi, K. and Sato, K. and Seki, T. and Iguchi, H. and Adachi, K. and Hidekuma, S. and Hirokura, S. and Iwasaki, K. and Ido, T. and Kojima, M. and Koong, J. and Kumazawa, R. and Kuramoto, H. and Minami, T. and Nomura, I. and Sakakita, H. and Sasao, M. and Sato, K.N. and Tsuzuki, T. and Xu, J. and Yamada, I. and Watari, T."}, month = {Nov}, note = {"Multiple and small sample-volume measurements of the density turbulence and potential profile measurement in tokamak plasmas were conducted by a heavy ion beam probe. The obtained wavenumber/frequency spectrum S(k,omega) shows that the cross-section of NBI heated plasmas is divided into three regions of different turbulence characteristics. Outside the reversal layer of poloidal propagation direction of density turbulence, a low-frequency and low-wavenumber mode with ion diamagnetic drift direction dominates. The region encircled by the reversal layer is divided into two parts at nearly perpendicular NBI heating, the region where the propagation velocity is near the E_r/B_t poloidal rotation velocity and the bad-curvature region of very small wavenumber and high propagation velocity. The region of high propagation velocity, found in NBI plasmas, disappears in ohmic plasmas. In addition, a small component which propagates in the ion diamagnetic drift direction is observed in NBI plasmas."}, title = {Density Fluctuation in JIPP T-IIU Tokamak Plasmas Measured by a Heavy Ion Beam Probe}, year = {1996} }