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Title: Effects of the q profile on toroidal rotation in Alcator C-Mod LHCD plasmas

Abstract

Changes in the core toroidal rotation profiles following injection of lower hybrid (LH) waves have been documented in Alcator C-Mod plasmas. Shot by shot scans of LH input power have been performed at fixed magnetic field and electron density for several plasma currents. For sawtoothing target plasmas, if the input power is low enough that the central safety factor q0 remains below 1, the change in the core rotation is in the counter-current direction, consistent in sign, magnitude and LH power scaling with direct momentum input from the LH waves. If the power level is high enough that there are significant changes to the q profile, including the termination of sawtooth oscillations, the change in the toroidal rotation is in the co-current direction, consistent with changes in the momentum flux through its dependence on the current density profile. Furthermore, the direction of the rotation changes depends on whether q0 is below or above unity, and seemingly not on the magnetic shear, nor the Ohmic confinement regime of the target plasma.

Authors:
 [1];  [1];  [1];  [1];  [2];  [1];  [1];  [1];  [2];  [3];  [1];  [1];  [1];  [1];  [1];  [1];  [1];  [4];  [1]
  1. Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)
  2. Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)
  3. CEA, IRFM, St. Paul-lez-Durance (France)
  4. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
1319213
DOE Contract Number:  
AC05-00OR22725
Resource Type:
Journal Article
Journal Name:
Nuclear Fusion
Additional Journal Information:
Journal Volume: 56; Journal Issue: 3; Journal ID: ISSN 0029-5515
Publisher:
IOP Science
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; rotation; q profile; lower hybrid current drive; tokamak

Citation Formats

Rice, J. E., Gao, C., Mumgaard, R., Parker, R. R., Scott, S. D., Shiraiwa, S., Wallace, G. M., Bonoli, P. T., Delgado-Aparicio, L., Fenzi, C., Granetz, R. S., Greenwald, M. J., Hubbard, A. E., Hughes, J. W., Irby, J. H., Lee, J. P., Marmar, E. S., Reinke, M. L., and Wolfe, S. M. Effects of the q profile on toroidal rotation in Alcator C-Mod LHCD plasmas. United States: N. p., 2016. Web. doi:10.1088/0029-5515/56/3/036015.
Rice, J. E., Gao, C., Mumgaard, R., Parker, R. R., Scott, S. D., Shiraiwa, S., Wallace, G. M., Bonoli, P. T., Delgado-Aparicio, L., Fenzi, C., Granetz, R. S., Greenwald, M. J., Hubbard, A. E., Hughes, J. W., Irby, J. H., Lee, J. P., Marmar, E. S., Reinke, M. L., & Wolfe, S. M. Effects of the q profile on toroidal rotation in Alcator C-Mod LHCD plasmas. United States. https://doi.org/10.1088/0029-5515/56/3/036015
Rice, J. E., Gao, C., Mumgaard, R., Parker, R. R., Scott, S. D., Shiraiwa, S., Wallace, G. M., Bonoli, P. T., Delgado-Aparicio, L., Fenzi, C., Granetz, R. S., Greenwald, M. J., Hubbard, A. E., Hughes, J. W., Irby, J. H., Lee, J. P., Marmar, E. S., Reinke, M. L., and Wolfe, S. M. 2016. "Effects of the q profile on toroidal rotation in Alcator C-Mod LHCD plasmas". United States. https://doi.org/10.1088/0029-5515/56/3/036015.
@article{osti_1319213,
title = {Effects of the q profile on toroidal rotation in Alcator C-Mod LHCD plasmas},
author = {Rice, J. E. and Gao, C. and Mumgaard, R. and Parker, R. R. and Scott, S. D. and Shiraiwa, S. and Wallace, G. M. and Bonoli, P. T. and Delgado-Aparicio, L. and Fenzi, C. and Granetz, R. S. and Greenwald, M. J. and Hubbard, A. E. and Hughes, J. W. and Irby, J. H. and Lee, J. P. and Marmar, E. S. and Reinke, M. L. and Wolfe, S. M.},
abstractNote = {Changes in the core toroidal rotation profiles following injection of lower hybrid (LH) waves have been documented in Alcator C-Mod plasmas. Shot by shot scans of LH input power have been performed at fixed magnetic field and electron density for several plasma currents. For sawtoothing target plasmas, if the input power is low enough that the central safety factor q0 remains below 1, the change in the core rotation is in the counter-current direction, consistent in sign, magnitude and LH power scaling with direct momentum input from the LH waves. If the power level is high enough that there are significant changes to the q profile, including the termination of sawtooth oscillations, the change in the toroidal rotation is in the co-current direction, consistent with changes in the momentum flux through its dependence on the current density profile. Furthermore, the direction of the rotation changes depends on whether q0 is below or above unity, and seemingly not on the magnetic shear, nor the Ohmic confinement regime of the target plasma.},
doi = {10.1088/0029-5515/56/3/036015},
url = {https://www.osti.gov/biblio/1319213}, journal = {Nuclear Fusion},
issn = {0029-5515},
number = 3,
volume = 56,
place = {United States},
year = {Tue Feb 09 00:00:00 EST 2016},
month = {Tue Feb 09 00:00:00 EST 2016}
}

Works referenced in this record:

Intrinsic torque reversals induced by magnetic shear effects on the turbulence spectrum in tokamak plasmasa)
journal, May 2015


Observation of Anomalous Momentum Transport in Tokamak Plasmas with No Momentum Input
journal, November 2003


Full wave effects on the lower hybrid wave spectrum and driven current profile in tokamak plasmas
journal, August 2011


Charge exchange spectroscopy measurements of ion temperature and toroidal rotation in JET
journal, December 1989


Bulk plasma rotation in the TCV tokamak in the absence of external momentum input
journal, November 2007


Reconstruction of current profile parameters and plasma shapes in tokamaks
journal, November 1985


Error field mode studies on JET, COMPASS-D and DIII-D, and implications for ITER
journal, November 1999


Observations of anomalous momentum transport in Alcator C-Mod plasmas with no momentum input
journal, February 2004


Experimental demonstration of an up-down asymmetry effect on intrinsic rotation in the TCV tokamak
journal, November 2010


Investigations of LHCD induced plasma rotation in Tore Supra
journal, October 2015


Observation of Self-Generated Flows in Tokamak Plasmas with Lower-Hybrid-Driven Current
journal, January 2009


Edge Temperature Gradient as Intrinsic Rotation Drive in Alcator C -Mod Tokamak Plasmas
journal, May 2011


Intrinsic Toroidal Rotation, Density Peaking, and Turbulence Regimes in the Core of Tokamak Plasmas
journal, November 2011


Spontaneous L-mode plasma rotation scaling in the TCV tokamak
journal, May 2008


Estimation of the ion toroidal rotation source due to momentum transfer from Lower Hybrid waves in Alcator C-Mod
conference, January 2011


The Alcator C-Mod Program
journal, April 2007


On the toroidal plasma rotations induced by lower hybrid waves
journal, February 2013


Rotation Reversal Bifurcation and Energy Confinement Saturation in Tokamak Ohmic L -Mode Plasmas
journal, December 2011


Toroidal plasma rotation in the TCV tokamak
journal, April 2006


Large amplitude quasi-stationary MHD modes in JET
journal, June 1988


Effects of Magnetic Shear on Toroidal Rotation in Tokamak Plasmas with Lower Hybrid Current Drive
journal, September 2013


Response of toroidal rotation velocity to electron cyclotron wave injection in JT-60U
journal, April 2006


Spatially resolved high resolution x-ray spectroscopy for magnetically confined fusion plasmas (invited)
journal, October 2008


Nonaxisymmetric field effects on Alcator C-Mod
journal, May 2005


Co- and counter-current rotation in Tore Supra lower hybrid current drive plasmas
journal, July 2014


Wave-Particle Studies in the Ion Cyclotron and Lower Hybrid Ranges of Frequencies in Alcator C-Mod
journal, April 2007


X-ray imaging crystal spectroscopy for use in plasma transport research
journal, November 2012


The effect of diamagnetic flows on turbulent driven ion toroidal rotation
journal, May 2014


Diagnostic Systems on Alcator C-Mod
journal, April 2007


Physics of non-diffusive turbulent transport of momentum and the origins of spontaneous rotation in tokamaks
journal, March 2009


Observation of Spontaneous Toroidal Rotation Inversion in Ohmically Heated Tokamak Plasmas
journal, December 2006


Ohmic energy confinement saturation and core toroidal rotation reversal in Alcator C-Mod plasmas
journal, May 2012


Observation of Cocurrent Toroidal Rotation in the EAST Tokamak with Lower-Hybrid Current Drive
journal, June 2011


Intrashot motional Stark effect calibration technique for lower hybrid current drive experiments
journal, March 2010


Intrinsic Toroidal Rotation, Density Peaking, and Turbulence Regimes in the Core of Tokamak Plasmas
journal, November 2011


Observation of Spontaneous Toroidal Rotation Inversion in Ohmically Heated Tokamak Plasmas
journal, December 2006


Bulk plasma rotation in the TCV tokamak in the absence of external momentum input
journal, November 2007


Rotation Reversal Bifurcation and Energy Confinement Saturation in Tokamak Ohmic L -Mode Plasmas
journal, December 2011


Edge Temperature Gradient as Intrinsic Rotation Drive in Alcator C -Mod Tokamak Plasmas
journal, May 2011


Effects of Magnetic Shear on Toroidal Rotation in Tokamak Plasmas with Lower Hybrid Current Drive
journal, September 2013


Response of toroidal rotation velocity to electron cyclotron wave injection in JT-60U
journal, April 2006


Observation of Cocurrent Toroidal Rotation in the EAST Tokamak with Lower-Hybrid Current Drive
journal, June 2011


Observation of Self-Generated Flows in Tokamak Plasmas with Lower-Hybrid-Driven Current
journal, January 2009


Error field mode studies on JET, COMPASS-D and DIII-D, and implications for ITER
journal, November 1999


The Alcator C-Mod Program
journal, April 2007


Wave-Particle Studies in the Ion Cyclotron and Lower Hybrid Ranges of Frequencies in Alcator C-Mod
journal, April 2007


Diagnostic Systems on Alcator C-Mod
journal, April 2007


Observation of Anomalous Momentum Transport in Tokamak Plasmas with No Momentum Input
journal, November 2003