| PHYSICS OF GASES, PLASMAS, AND ELECTRIC DISCHARGES |
|
|
|
|
Electron Cyclotron Emission Imaging Observations of m/n=1/1 and Higher Harmonic Modes during Sawtooth Oscillation in ICRF Heating Plasma on EAST |
| AZAM Hussain, GAO Bing-Xi, LIU Wan-Dong, XIE Jin-Lin**, the EAST Team |
Key Laboratory of Basic Plasma Physics, Department of Modern Physics, University of Science and Technology of China, Hefei 230026
|
|
| Cite this article: |
|
AZAM Hussain, GAO Bing-Xi, LIU Wan-Dong et al 2015 Chin. Phys. Lett. 32 065201 |
|
|
|
|
Abstract The m/n=1/1 and its higher harmonic modes are observed in sawtooth oscillations by using the novel high-resolution 2D ECE imaging system on the experimental advanced superconducting Tokamak (EAST). Higher harmonic modes are appearing for a short time during the crash phase of sawtooth oscillation in lower βp plasma, which is not the preferable position in the poloidal cross section. These modes generate sharp pressure points on the inversion radius during the crash phase of sawtooth oscillation. Furthermore, reconnection events proceed in two distinctive phases. In the first phase, a small amount of heat is expelled through the weak reconnection while in the second phase the remaining large quantity of heat and particles emerged rapidly from the hot core to the peripheral region of the inversion radius. In addition, these harmonic modes are only found before and after the ICRF pulse, while in the ICRF pulse only the (1,1) mode exists in the sawtooth oscillation.
|
|
|
Received: 05 January 2015
Published: 30 June 2015
|
|
| PACS: |
52.55.Fa
|
(Tokamaks, spherical tokamaks)
|
| |
52.70.Gw
|
(Radio-frequency and microwave measurements)
|
| |
52.35.Vd
|
(Magnetic reconnection)
|
| |
52.35.Py
|
(Macroinstabilities (hydromagnetic, e.g., kink, fire-hose, mirror, ballooning, tearing, trapped-particle, flute, Rayleigh-Taylor, etc.))
|
|
|
|
|
|
[1] Von Goeler S, Stodiek W and Sauthoff N 1974 Phys. Rev. Lett. 33 1201
[2] Hastie R J 1998 Astrophys. Space Sci. 1 177
[3] Kadomtsev B B 1975 Sov. J. Plasma Phys. 1 710
[4] Wesson J A 1986 Plasma Phys. Control. Fusion 28 243
[5] Nishimura Y, Callen J D and Hegna C C 1999 Phys. Plasmas 6 4685
[6] Nagayama Y, Yamada M, Park W, Fredrickson E D, Janos A C, McGuire K M and Taylor G 1996 Phys. Plasmas 3 1647
[7] Yamaguchi S, Igami H, Tanaka H and Maekawa T 2004 Plasma Phys. Control. Fusion 46 1163
[8] Xu X Y, Wang J, Wen Y, Yu Y, Liu A, Lan T, Wan B, Gao X, Sun Y, Luhmann N C, Domier C W, Xia Z G and Shen Z 2009 Plasma Phys. Control. Fusion 52 015008
[9] Yamada M, Levinton F M, Pomphrey N, Budny R, Manickam J and Nagayama Y 1994 Phys. Plasmas 1 3269
[10] Park H K, Mazzucato E, Luhmann N C, Domier C W, Xia Z, Munsat T, Donneí A J H, Classen I G J and van de Pol M J 2006 Phys. Plasmas 13 055907
[11] Munsat T, Park H K, Classen I G J, Domier C W, Donné A J H, Luhmann N C, Mazzucato E and van de Pol M J 2007 Nucl. Fusion 47 L31
[12] Tobias B, Kong X, Liang T, Spear A, Domier C W, Luhmann N C, Classen I G J, Boom J E, Van De Pol M J, Jaspers R, Donné A J H, Park H K and Munsat T 2009 Rev. Sci. Instrum. 80 093502
[13] Park H K, Luhmann N C, Donné A J H, Classen I G J, Domier C W, Mazzucato E, Munsat T, van de Pol M J and Xia Z 2006 Phys. Rev. Lett. 96 195003
[14] Janicki C, Decoste R, Simm C and Varennes T De 1989 Phys. Rev. Lett. 62 3038
[15] Yamaguchi S, Igami H, Tanaka H and Maekawa T 2004 Phys. Rev. Lett. 93 045005
[16] Igochine V, Dumbrajs O, Zohm H, Flaws A and the A U Team 2007 Nucl. Fusion 47 23 |
|
Viewed |
|
|
|
Full text
|
|
|
|
|
Abstract
|
|
|
|
|
