Investigations of the radial propagation of blob-like structure in a non-confined electron cyclotron resonance heated plasma on Q-shu University Experiment with a Steady-State Spherical Tokamak

Ogata Ryota

Hanada Kazuaki

Nishino Nobuhiro

Liu Haiqing

Zushi Hideki

Ishiguro Masaki

Ikeda Teruaki

Nakamura Kazuo

Fujisawa Akihide

Idei Hiroshi

Hasegawa Makoto

Kawasaki Shoji

Nakashima Hisatoshi

Higashijima Aki

QUEST Group

Physics of Plasmas

A study of radial propagation and electric fields induced by charge separation in blob-like structures has been performed in a non-confined cylindrical electron cyclotron resonance heating plasma on Q-shu University Experiment with a Steady-State Spherical Tokamak using a fast-speed camera and a Langmuir probe. The radial propagation of the blob-like structures is found to be driven by E × B drift. Moreover, these blob-like structures were found to have been accelerated, and the property of the measured radial velocities agrees with the previously proposed model [C. Theiler et al., Phys. Rev. Lett. 103, 065001 (2009)]. Although the dependence of the radial velocity on the connection length of the magnetic field appeared to be different, a plausible explanation based on enhanced short-circuiting of the current path can be proposed.

Physics [ 420 ]

eng

American Institute of Physics

(c) 2011 American Institute of Physics

[ISSN] 1070-664X

[DOI] 10.1063/1.3640494

[NCID] AA10987555

[DOI] http://dx.doi.org/10.1063/1.3640494