Smoothness of turbulent transport across a minimum-q surface

Some controversy exists over the role of weak or reversed shear in the formation of internal transport barriers. One theory attributes the formation of internal transport barriers to a gap in global wave structures in the minimum-q region. It is shown that in general no such gap exists, and that energy transport is smooth and increasing across such a minimum-q region.

[1]  Charlson C. Kim,et al.  Comparisons and physics basis of tokamak transport models and turbulence simulations , 2000 .

[2]  D. Frenkel,et al.  Algebraic methods to compute Mathieu functions , 2001 .

[3]  W. Horton,et al.  Gyrokinetic study of ion temperature gradient instability in vicinity of flux surfaces with reversed magnetic shear , 2001 .

[4]  J. Taylor,et al.  Shear damping of two-dimensional drift waves in a large-aspect-ratio tokamak , 1979 .

[5]  First principles model of internal transport barriers in negative central shear discharges , 2001 .

[6]  F. Romanelli,et al.  The radial structure of the ion‐temperature‐gradient‐driven mode , 1993 .

[7]  Yasuaki Kishimoto,et al.  Discontinuity model for internal transport barrier formation in reversed magnetic shear plasmas , 2000 .

[8]  Jeff M. Candy,et al.  Gyrokinetic turbulence simulation of profile shear stabilization and broken gyroBohm scaling , 2002 .

[9]  F. Jenko,et al.  Electron temperature gradient turbulence. , 2000, Physical review letters.

[10]  S. Mahajan,et al.  Study of microinstabilities in toroidal plasmas with negative magnetic shear , 1996 .

[11]  F. Jenko,et al.  Prediction of significant tokamak turbulence at electron gyroradius scales. , 2002, Physical review letters.

[12]  Mike Kotschenreuther,et al.  Comparison of initial value and eigenvalue codes for kinetic toroidal plasma instabilities , 1995 .

[13]  Chio Cheng,et al.  Electrostatic drift wave eigenmodes in tokamaks , 1981 .

[14]  Jose Milovich,et al.  Toroidal gyro‐Landau fluid model turbulence simulations in a nonlinear ballooning mode representation with radial modes , 1994 .

[15]  Irene A. Stegun,et al.  Handbook of Mathematical Functions. , 1966 .

[16]  Slablike ion temperature gradient driven mode in reversed shear tokamaks , 2002 .

[17]  Gregory W. Hammett,et al.  Advances in the simulation of toroidal gyro Landau fluid model turbulence , 1995 .

[18]  Shinji Tokuda,et al.  Global gyrokinetic simulation of ion temperature gradient driven turbulence in plasmas using a canonical Maxwellian distribution , 2003 .

[19]  R. Waltz,et al.  Anomalous transport scaling in the DIII-D tokamak matched by supercomputer simulation. , 2003, Physical review letters.

[20]  C. Bourdelle,et al.  Global simulations of ion turbulence with magnetic shear reversal , 2001 .