ICRF mode conversion in three-ion species heating experiment and in flow drive experiment on the Alcator C-Mod tokamak

Lin, Y.; Wukitch, S. J.; Edlund, E.; Ennever, P.; Hubbard, A. E.; Porkolab, M.; Rice, J.; Wright, J.

doi:10.7910/DVN/KF4VRD

Title: ICRF mode conversion in three-ion species heating experiment and in flow drive experiment on the Alcator C-Mod tokamak

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Abstract

In recent three-ion species (majority D and H plus a trace level of 3He) ICRF heating experiments on Alcator C-Mod, double mode conversion on both sides of the 3He cyclotron resonance has been observed using the phase contrast imaging (PCI) system. The MC locations are used to estimate the species concentrations in the plasma. Simulation using TORIC shows that with the 3He level <1%, most RF power is absorbed by the 3He ions and the process can generate energetic 3He ions. In mode conversion (MC) flow drive experiment in D(3He) plasma at 8 T, MC waves were also monitored by PCI. The MC ion cyclotron wave (ICW) amplitude and wavenumber kR have been found to correlate with the flow drive force. The MC efficiency, wave-number k of the MC ICW and their dependence on plasma parameters like Te0 have been studied. Based on the experimental observation and numerical study of the dispersion solutions, a hypothesis of the flow drive mechanism has been proposed.

Authors:: Lin, Y.; Wukitch, S. J.; Edlund, E.; Ennever, P.; Hubbard, A. E.; Porkolab, M.; Rice, J.; Wright, J.

Publication Date:: 2018-10-04

DOE Contract Number:: FC02-99ER54512

Research Org.:: Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States). Plasma Science and Fusion Center

Sponsoring Org.:: USDOE Office of Science (SC), Fusion Energy Sciences (FES)

Subject:: 70 PLASMA PHYSICS AND FUSION TECHNOLOGY

OSTI Identifier:: 1878758

DOI:: https://doi.org/10.7910/DVN/KF4VRD

Citation Formats


                    Lin, Y., Wukitch, S. J., Edlund, E., Ennever, P., Hubbard, A. E., Porkolab, M., Rice, J., and Wright, J. ICRF mode conversion in three-ion species heating experiment and in flow drive experiment on the Alcator C-Mod tokamak.  United States: N. p., 2018. 
        Web.  doi:10.7910/DVN/KF4VRD.

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                    Lin, Y., Wukitch, S. J., Edlund, E., Ennever, P., Hubbard, A. E., Porkolab, M., Rice, J., & Wright, J. ICRF mode conversion in three-ion species heating experiment and in flow drive experiment on the Alcator C-Mod tokamak.  United States.  doi:https://doi.org/10.7910/DVN/KF4VRD

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                    Lin, Y., Wukitch, S. J., Edlund, E., Ennever, P., Hubbard, A. E., Porkolab, M., Rice, J., and Wright, J. 2018.  
"ICRF mode conversion in three-ion species heating experiment and in flow drive experiment on the Alcator C-Mod tokamak".  United States.  doi:https://doi.org/10.7910/DVN/KF4VRD.  https://www.osti.gov/servlets/purl/1878758. Pub date:Thu Oct 04 00:00:00 EDT 2018

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@article{osti_1878758,

  title        = {ICRF mode conversion in three-ion species heating experiment and in flow drive experiment on the Alcator C-Mod tokamak},

  author       = {Lin, Y. and Wukitch, S. J. and Edlund, E. and Ennever, P. and Hubbard, A. E. and Porkolab, M. and Rice, J. and Wright, J.},

  abstractNote = {In recent three-ion species (majority D and H plus a trace level of 3He) ICRF heating experiments on Alcator C-Mod, double mode conversion on both sides of the 3He cyclotron resonance has been observed using the phase contrast imaging (PCI) system. The MC locations are used to estimate the species concentrations in the plasma. Simulation using TORIC shows that with the 3He level <1%, most RF power is absorbed by the 3He ions and the process can generate energetic 3He ions. In mode conversion (MC) flow drive experiment in D(3He) plasma at 8 T, MC waves were also monitored by PCI. The MC ion cyclotron wave (ICW) amplitude and wavenumber kR have been found to correlate with the flow drive force. The MC efficiency, wave-number k of the MC ICW and their dependence on plasma parameters like Te0 have been studied. Based on the experimental observation and numerical study of the dispersion solutions, a hypothesis of the flow drive mechanism has been proposed.},

  doi          = {10.7910/DVN/KF4VRD},

  journal      = {},

  number       = ,

  volume       = ,

  place        = {United States},

  year         = {2018},

  month        = {10}

}

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DOI: https://doi.org/10.7910/DVN/KF4VRD

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