Plasma equilibrium based on RF-driven current profile without assuming nested magnetic surfaces on QUEST

K. Nakamura, M. M. Alam, Y. Z. Jiang, O. Mitarai, K. Kurihara, Y. Kawamata, M. Sueoka, M. Takechi, M. Hasegawa, K. Tokunaga, K. Araki, H. Zushi, K. Hanada, A. Fujisawa, H. Idei, Y. Nagashima, S. Kawasaki, H. Nakashima, A. Higashijima, T. NagataA. Fukuyama

Research output: Contribution to journalArticle

Abstract

In the present RF-driven (ECCD) steady-state plasma on QUEST, the plasma current seems to flow in the open magnetic surface outside of the closed magnetic surface in the low-field region according to the plasma current fitting (PCF) method. The current in the open magnetic surface is due to the orbit-driven current by high-energy particles in the RF-driven plasma. High-energy particles guiding center orbits are calculated as contour plots of conserved variables in the Hamiltonian formulation considering particles in the initial position with different energies and pitch angles satisfying the resonance condition. A negative current appears near the magnetic axis, and a hollow current profile is expected even if the pressure driven current is considered. The equilibrium is fitted within nested magnetic surfaces by J-EFIT coded by MATLAB using the hollow current profile shift toward the low-field region. Although the plasma boundary shape reflects the plasma current density profile, the equilibrium shape fitted by J-EFIT does not coincide with the orbit-driven current profile. However, introducing an extension of the current profile without assuming nested contours into the J-EFIT code appropriately fits the plasma shape with the hollow current profile to the measured magnetic data.

Original languageEnglish
Pages (from-to)532-534
Number of pages3
JournalFusion Engineering and Design
Volume123
DOIs
Publication statusPublished - Nov 2017

Fingerprint

Plasmas
Orbits
Hamiltonians
MATLAB
Current density

All Science Journal Classification (ASJC) codes

  • Civil and Structural Engineering
  • Nuclear Energy and Engineering
  • Materials Science(all)
  • Mechanical Engineering

Cite this

Nakamura, K., Alam, M. M., Jiang, Y. Z., Mitarai, O., Kurihara, K., Kawamata, Y., ... Fukuyama, A. (2017). Plasma equilibrium based on RF-driven current profile without assuming nested magnetic surfaces on QUEST. Fusion Engineering and Design, 123, 532-534. https://doi.org/10.1016/j.fusengdes.2017.05.070

Plasma equilibrium based on RF-driven current profile without assuming nested magnetic surfaces on QUEST. / Nakamura, K.; Alam, M. M.; Jiang, Y. Z.; Mitarai, O.; Kurihara, K.; Kawamata, Y.; Sueoka, M.; Takechi, M.; Hasegawa, M.; Tokunaga, K.; Araki, K.; Zushi, H.; Hanada, K.; Fujisawa, A.; Idei, H.; Nagashima, Y.; Kawasaki, S.; Nakashima, H.; Higashijima, A.; Nagata, T.; Fukuyama, A.

In: Fusion Engineering and Design, Vol. 123, 11.2017, p. 532-534.

Research output: Contribution to journalArticle

Nakamura, K, Alam, MM, Jiang, YZ, Mitarai, O, Kurihara, K, Kawamata, Y, Sueoka, M, Takechi, M, Hasegawa, M, Tokunaga, K, Araki, K, Zushi, H, Hanada, K, Fujisawa, A, Idei, H, Nagashima, Y, Kawasaki, S, Nakashima, H, Higashijima, A, Nagata, T & Fukuyama, A 2017, 'Plasma equilibrium based on RF-driven current profile without assuming nested magnetic surfaces on QUEST', Fusion Engineering and Design, vol. 123, pp. 532-534. https://doi.org/10.1016/j.fusengdes.2017.05.070
Nakamura, K. ; Alam, M. M. ; Jiang, Y. Z. ; Mitarai, O. ; Kurihara, K. ; Kawamata, Y. ; Sueoka, M. ; Takechi, M. ; Hasegawa, M. ; Tokunaga, K. ; Araki, K. ; Zushi, H. ; Hanada, K. ; Fujisawa, A. ; Idei, H. ; Nagashima, Y. ; Kawasaki, S. ; Nakashima, H. ; Higashijima, A. ; Nagata, T. ; Fukuyama, A. / Plasma equilibrium based on RF-driven current profile without assuming nested magnetic surfaces on QUEST. In: Fusion Engineering and Design. 2017 ; Vol. 123. pp. 532-534.
@article{05c7f1e003fb4d51bf5d16bd044f0807,
title = "Plasma equilibrium based on RF-driven current profile without assuming nested magnetic surfaces on QUEST",
abstract = "In the present RF-driven (ECCD) steady-state plasma on QUEST, the plasma current seems to flow in the open magnetic surface outside of the closed magnetic surface in the low-field region according to the plasma current fitting (PCF) method. The current in the open magnetic surface is due to the orbit-driven current by high-energy particles in the RF-driven plasma. High-energy particles guiding center orbits are calculated as contour plots of conserved variables in the Hamiltonian formulation considering particles in the initial position with different energies and pitch angles satisfying the resonance condition. A negative current appears near the magnetic axis, and a hollow current profile is expected even if the pressure driven current is considered. The equilibrium is fitted within nested magnetic surfaces by J-EFIT coded by MATLAB using the hollow current profile shift toward the low-field region. Although the plasma boundary shape reflects the plasma current density profile, the equilibrium shape fitted by J-EFIT does not coincide with the orbit-driven current profile. However, introducing an extension of the current profile without assuming nested contours into the J-EFIT code appropriately fits the plasma shape with the hollow current profile to the measured magnetic data.",
author = "K. Nakamura and Alam, {M. M.} and Jiang, {Y. Z.} and O. Mitarai and K. Kurihara and Y. Kawamata and M. Sueoka and M. Takechi and M. Hasegawa and K. Tokunaga and K. Araki and H. Zushi and K. Hanada and A. Fujisawa and H. Idei and Y. Nagashima and S. Kawasaki and H. Nakashima and A. Higashijima and T. Nagata and A. Fukuyama",
year = "2017",
month = "11",
doi = "10.1016/j.fusengdes.2017.05.070",
language = "English",
volume = "123",
pages = "532--534",
journal = "Fusion Engineering and Design",
issn = "0920-3796",
publisher = "Elsevier BV",

}

TY - JOUR

T1 - Plasma equilibrium based on RF-driven current profile without assuming nested magnetic surfaces on QUEST

AU - Nakamura, K.

AU - Alam, M. M.

AU - Jiang, Y. Z.

AU - Mitarai, O.

AU - Kurihara, K.

AU - Kawamata, Y.

AU - Sueoka, M.

AU - Takechi, M.

AU - Hasegawa, M.

AU - Tokunaga, K.

AU - Araki, K.

AU - Zushi, H.

AU - Hanada, K.

AU - Fujisawa, A.

AU - Idei, H.

AU - Nagashima, Y.

AU - Kawasaki, S.

AU - Nakashima, H.

AU - Higashijima, A.

AU - Nagata, T.

AU - Fukuyama, A.

PY - 2017/11

Y1 - 2017/11

N2 - In the present RF-driven (ECCD) steady-state plasma on QUEST, the plasma current seems to flow in the open magnetic surface outside of the closed magnetic surface in the low-field region according to the plasma current fitting (PCF) method. The current in the open magnetic surface is due to the orbit-driven current by high-energy particles in the RF-driven plasma. High-energy particles guiding center orbits are calculated as contour plots of conserved variables in the Hamiltonian formulation considering particles in the initial position with different energies and pitch angles satisfying the resonance condition. A negative current appears near the magnetic axis, and a hollow current profile is expected even if the pressure driven current is considered. The equilibrium is fitted within nested magnetic surfaces by J-EFIT coded by MATLAB using the hollow current profile shift toward the low-field region. Although the plasma boundary shape reflects the plasma current density profile, the equilibrium shape fitted by J-EFIT does not coincide with the orbit-driven current profile. However, introducing an extension of the current profile without assuming nested contours into the J-EFIT code appropriately fits the plasma shape with the hollow current profile to the measured magnetic data.

AB - In the present RF-driven (ECCD) steady-state plasma on QUEST, the plasma current seems to flow in the open magnetic surface outside of the closed magnetic surface in the low-field region according to the plasma current fitting (PCF) method. The current in the open magnetic surface is due to the orbit-driven current by high-energy particles in the RF-driven plasma. High-energy particles guiding center orbits are calculated as contour plots of conserved variables in the Hamiltonian formulation considering particles in the initial position with different energies and pitch angles satisfying the resonance condition. A negative current appears near the magnetic axis, and a hollow current profile is expected even if the pressure driven current is considered. The equilibrium is fitted within nested magnetic surfaces by J-EFIT coded by MATLAB using the hollow current profile shift toward the low-field region. Although the plasma boundary shape reflects the plasma current density profile, the equilibrium shape fitted by J-EFIT does not coincide with the orbit-driven current profile. However, introducing an extension of the current profile without assuming nested contours into the J-EFIT code appropriately fits the plasma shape with the hollow current profile to the measured magnetic data.

UR - http://www.scopus.com/inward/record.url?scp=85020398193&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85020398193&partnerID=8YFLogxK

U2 - 10.1016/j.fusengdes.2017.05.070

DO - 10.1016/j.fusengdes.2017.05.070

M3 - Article

AN - SCOPUS:85020398193

VL - 123

SP - 532

EP - 534

JO - Fusion Engineering and Design

JF - Fusion Engineering and Design

SN - 0920-3796

ER -