Correlation ECE diagnostic in Alcator C-Mod

Sung, C.; White, A. E.; Howard, N. T.; Mikkelsen, D.; Irby, J.; Leccacorvi, R.; Vieira, R.; Oi, C.; Rice, J.; Reinke, M.; Gao, C.; Ennever, P.; Porkolab, M.; Churchill, R.; Theiler, C.; Walk, J.; Hughes, J.; Hubbard, A.; Greenwald, M.

doi:10.1051/epjconf/20158703007

Title: Correlation ECE diagnostic in Alcator C-Mod

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Abstract

Correlation ECE (CECE) is a diagnostic technique that allows measurement of small amplitude electron temperature, Te, fluctuations through standard cross-correlation analysis methods. In Alcator C-Mod, a new CECE diagnostic has been installed[Sung RSI 2012], and interesting phenomena have been observed in various plasma conditions. We find that local Te fluctuations near the edge (ρ ~ 0:8) decrease across the linearto- saturated ohmic confinement transition, with fluctuations decreasing with increasing plasma density[Sung NF 2013], which occurs simultaneously with rotation reversals[Rice NF 2011]. Te fluctuations are also reduced across core rotation reversals with an increase of plasma density in RF heated L-mode plasmas, which implies that the same physics related to the reduction of Te fluctuations may be applied to both ohmic and RF heated L-mode plasmas. In I-mode plasmas, we observe the reduction of core Te fluctuations, which indicates changes of turbulence occur not only in the pedestal region but also in the core across the L/I transition[White NF 2014]. The present CECE diagnostic system in C-Mod and these experimental results are described in this paper.

Authors:

Sung, C. ^[1]; White, A. E. ^[1]; Howard, N. T. ^[1]; Mikkelsen, D. ^[2]; Irby, J. ^[1]; Leccacorvi, R. ^[1]; Vieira, R. ^[1]; Oi, C. ^[1]; Rice, J. ^[1]; Reinke, M. ^[1]; Gao, C. ^[1]; Ennever, P. ^[1]; Porkolab, M. ^[1]; Churchill, R. ^[1]; Theiler, C. ^[1]; Walk, J. ^[1]; Hughes, J. ^[1]; Hubbard, A. ^[1]; Greenwald, M. ^[1]

Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States). Plasma Science and Fusion Center
Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)

Publication Date:: Thu Mar 12 00:00:00 EDT 2015

Research Org.:: Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)

Sponsoring Org.:: USDOE

OSTI Identifier:: 1214643

Grant/Contract Number:: AC02-09CH11466

Resource Type:: Accepted Manuscript

Journal Name:: EPJ Web of Conferences

Additional Journal Information:: Journal Volume: 87; Journal ID: ISSN 2100-014X

Publisher:: EDP Sciences

Country of Publication:: United States

Language:: English

Subject:: 70 PLASMA PHYSICS AND FUSION TECHNOLOGY

Citation Formats


                    Sung, C., White, A. E., Howard, N. T., Mikkelsen, D., Irby, J., Leccacorvi, R., Vieira, R., Oi, C., Rice, J., Reinke, M., Gao, C., Ennever, P., Porkolab, M., Churchill, R., Theiler, C., Walk, J., Hughes, J., Hubbard, A., and Greenwald, M. Correlation ECE diagnostic in Alcator C-Mod.  United States: N. p., 2015. 
Web.  doi:10.1051/epjconf/20158703007.

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                    Sung, C., White, A. E., Howard, N. T., Mikkelsen, D., Irby, J., Leccacorvi, R., Vieira, R., Oi, C., Rice, J., Reinke, M., Gao, C., Ennever, P., Porkolab, M., Churchill, R., Theiler, C., Walk, J., Hughes, J., Hubbard, A., & Greenwald, M. Correlation ECE diagnostic in Alcator C-Mod.  United States.  https://doi.org/10.1051/epjconf/20158703007

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                    Sung, C., White, A. E., Howard, N. T., Mikkelsen, D., Irby, J., Leccacorvi, R., Vieira, R., Oi, C., Rice, J., Reinke, M., Gao, C., Ennever, P., Porkolab, M., Churchill, R., Theiler, C., Walk, J., Hughes, J., Hubbard, A., and Greenwald, M. Thu .  
"Correlation ECE diagnostic in Alcator C-Mod".  United States.  https://doi.org/10.1051/epjconf/20158703007.  https://www.osti.gov/servlets/purl/1214643.

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@article{osti_1214643,

  title        = {Correlation ECE diagnostic in Alcator C-Mod},

  author       = {Sung, C. and White, A. E. and Howard, N. T. and Mikkelsen, D. and Irby, J. and Leccacorvi, R. and Vieira, R. and Oi, C. and Rice, J. and Reinke, M. and Gao, C. and Ennever, P. and Porkolab, M. and Churchill, R. and Theiler, C. and Walk, J. and Hughes, J. and Hubbard, A. and Greenwald, M.},

  abstractNote = {Correlation ECE (CECE) is a diagnostic technique that allows measurement of small amplitude electron temperature, Te, fluctuations through standard cross-correlation analysis methods. In Alcator C-Mod, a new CECE diagnostic has been installed[Sung RSI 2012], and interesting phenomena have been observed in various plasma conditions. We find that local Te fluctuations near the edge (ρ ~ 0:8) decrease across the linearto- saturated ohmic confinement transition, with fluctuations decreasing with increasing plasma density[Sung NF 2013], which occurs simultaneously with rotation reversals[Rice NF 2011]. Te fluctuations are also reduced across core rotation reversals with an increase of plasma density in RF heated L-mode plasmas, which implies that the same physics related to the reduction of Te fluctuations may be applied to both ohmic and RF heated L-mode plasmas. In I-mode plasmas, we observe the reduction of core Te fluctuations, which indicates changes of turbulence occur not only in the pedestal region but also in the core across the L/I transition[White NF 2014]. The present CECE diagnostic system in C-Mod and these experimental results are described in this paper.},

  doi          = {10.1051/epjconf/20158703007},

  journal      = {EPJ Web of Conferences},

  number       = ,

  volume       = 87,

  place        = {United States},

  year         = {Thu Mar 12 00:00:00 EDT 2015},

  month        = {Thu Mar 12 00:00:00 EDT 2015}

}

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