Anomalous transport in the H-mode pedestal of Alcator C-Mod discharges

Pankin, A. Y.; Hughes, J. W.; Greenwald, M. J.; Kritz, A. H.; Rafiq, T.

doi:10.7910/DVN/QADDLH

Title: Anomalous transport in the H-mode pedestal of Alcator C-Mod discharges

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Abstract

Anomalous transport in the H-mode pedestal region of five Alcator C-Mod discharges, representing a collisionality scan is analyzed. The understanding of anomalous transport in the pedestal region is important for the development of a comprehensive model for the H-mode pedestal slope. In this research, a possible role of the drift resistive inertial ballooning modes (Rafiq et al 2010 Phys. Plasmas 17 082511) in the edge of Alcator C-Mod discharges is analyzed. The stability analysis, carried out using the TRANSP code, indicates that the DRIBM modes are strongly unstable in Alcator C-Mod discharges with large electron collisionality. An improved interpretive analysis of H-mode pedestal experimental data is carried out utilizing the additive flux minimization technique (Pankin et al 2013 Phys. Plasmas 20 102501) together with the guiding-center neoclassical kinetic XGC0 code. The neoclassical and neutral physics are simulated in the XGC0 code and the anomalous fluxes are computed using the additive flux minimization technique. The anomalous fluxes are reconstructed and compared with each other for the collisionality scan Alcator C-Mod discharges. It is found that the electron thermal anomalous diffusivities at the pedestal top increase with the electron collisionality. This dependence can also point to the drift resistive inertial ballooning modesmore »« less

Authors:

Pankin, A. Y.; Hughes, J. W.; Greenwald, M. J.; Kritz, A. H.; Rafiq, T.

OSTI

Publication Date:: Fri Jun 04 04:00:00 UTC 2021

DOE Contract Number:: FC02-99ER54512; FG02-92ER54141; SC0008605; SC0012174; SC0013977; AC02-05CH11231

Research Org.:: Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States). Plasma Science and Fusion Center; Lehigh Univ., Bethlehem, PA (United States); Tech-X Corporation, Boulder, CO (United States)

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

Subject:: 70 PLASMA PHYSICS AND FUSION TECHNOLOGY

OSTI Identifier:: 1882663

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

Citation Formats


                    Pankin, A. Y., Hughes, J. W., Greenwald, M. J., Kritz, A. H., and Rafiq, T. Anomalous transport in the H-mode pedestal of Alcator C-Mod discharges.  United States: N. p., 2021. 
        Web.  doi:10.7910/DVN/QADDLH.

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                    Pankin, A. Y., Hughes, J. W., Greenwald, M. J., Kritz, A. H., & Rafiq, T. Anomalous transport in the H-mode pedestal of Alcator C-Mod discharges.  United States.  doi:https://doi.org/10.7910/DVN/QADDLH

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                    Pankin, A. Y., Hughes, J. W., Greenwald, M. J., Kritz, A. H., and Rafiq, T. 2021.  
"Anomalous transport in the H-mode pedestal of Alcator C-Mod discharges".  United States.  doi:https://doi.org/10.7910/DVN/QADDLH.  https://www.osti.gov/servlets/purl/1882663. Pub date:Fri Jun 04 04:00:00 UTC 2021

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@article{osti_1882663,

  title        = {Anomalous transport in the H-mode pedestal of Alcator C-Mod discharges},

  author       = {Pankin, A. Y. and Hughes, J. W. and Greenwald, M. J. and Kritz, A. H. and Rafiq, T.},

  abstractNote = {Anomalous transport in the H-mode pedestal region of five Alcator C-Mod discharges, representing a collisionality scan is analyzed. The understanding of anomalous transport in the pedestal region is important for the development of a comprehensive model for the H-mode pedestal slope. In this research, a possible role of the drift resistive inertial ballooning modes (Rafiq et al 2010 Phys. Plasmas 17 082511) in the edge of Alcator C-Mod discharges is analyzed. The stability analysis, carried out using the TRANSP code, indicates that the DRIBM modes are strongly unstable in Alcator C-Mod discharges with large electron collisionality. An improved interpretive analysis of H-mode pedestal experimental data is carried out utilizing the additive flux minimization technique (Pankin et al 2013 Phys. Plasmas 20 102501) together with the guiding-center neoclassical kinetic XGC0 code. The neoclassical and neutral physics are simulated in the XGC0 code and the anomalous fluxes are computed using the additive flux minimization technique. The anomalous fluxes are reconstructed and compared with each other for the collisionality scan Alcator C-Mod discharges. It is found that the electron thermal anomalous diffusivities at the pedestal top increase with the electron collisionality. This dependence can also point to the drift resistive inertial ballooning modes as the modes that drive the anomalous transport in the plasma edge of highly collisional discharges.},

  doi          = {10.7910/DVN/QADDLH},

  journal      = {},

  number       = ,

  volume       = ,

  place        = {United States},

  year         = {Fri Jun 04 04:00:00 UTC 2021},

  month        = {Fri Jun 04 04:00:00 UTC 2021}

}

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

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