[Table of Contents]

Plasma and Fusion Research

Volume 8, 2401130 (2013)

Regular Articles


Experimental Study of Two-Fluid Effect during Magnetic Reconnection in the UTST Merging Experiment
Kotaro YAMASAKI, Shuji KAMIO1), Koichiro TAKEMURA, Qinghong CAO, Takenori G. WATANABE, Hirotomo ITAGAKI, Takuma YAMADA2), Michiaki INOMOTO and Yasushi ONO
The University of Tokyo, Kashiwa 277-8561, Japan
1)
National Institute for Fusion Science, 322-6 Oroshi-cho, Toki 509-5292, Japan
2)
Faculty of Arts and Science, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan
(Received 8 December 2012 / Accepted 17 July 2013 / Published 26 September 2013)

Abstract

Radial profile of floating potential inside the current sheet was measured for the purpose of investigating the two-fluid (Hall) effect during magnetic reconnection in the UTST merging experiment. During magnetic reconnection, the floating potential drop was formed spontaneously inside the current sheet, forming a steep electric potential gradient on its both downstream areas. Magnetic probe array measurement indicates that this potential drop appears spontaneously when the reconnection rate rapidly increase due to change in current sheet structure. The IDS probe measurement observed outflow almost equal to poloidal Alfvén speed in radial direction from the X-point, where steep gradient of floating potential is formed. This fact suggests that ion acceleration/heating is caused by the steep potential gradient formed in the downstream by magnetized electrons.


Keywords

magnetic reconnection, spherical tokamak, plasma merging, two-fluid effect

DOI: 10.1585/pfr.8.2401130


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This paper may be cited as follows:

Kotaro YAMASAKI, Shuji KAMIO, Koichiro TAKEMURA, Qinghong CAO, Takenori G. WATANABE, Hirotomo ITAGAKI, Takuma YAMADA, Michiaki INOMOTO and Yasushi ONO, Plasma Fusion Res. 8, 2401130 (2013).