Research output: Contribution to journal › Article

**The stability of ballooning modes in tokamaks with internal transport barriers.** / Webster, A J ; Szwer, D J ; Wilson, H R .

Research output: Contribution to journal › Article

Webster, AJ, Szwer, DJ & Wilson, HR 2005, 'The stability of ballooning modes in tokamaks with internal transport barriers', *Physics of Plasmas*, vol. 12, no. 9, 092502, pp. -. https://doi.org/10.1063/1.2032742

Webster, A. J., Szwer, D. J., & Wilson, H. R. (2005). The stability of ballooning modes in tokamaks with internal transport barriers. *Physics of Plasmas*, *12*(9), -. [092502]. https://doi.org/10.1063/1.2032742

Webster AJ, Szwer DJ, Wilson HR. The stability of ballooning modes in tokamaks with internal transport barriers. Physics of Plasmas. 2005 Sep;12(9):-. 092502. https://doi.org/10.1063/1.2032742

@article{8812f5eb0d2c426d83595dfa20e31d03,

title = "The stability of ballooning modes in tokamaks with internal transport barriers",

abstract = "Modern tokamaks can produce transport barriers (TBs)-localized regions with an increased energy confinement. Previous studies have been unable to examine the stability of internal TBs to radially extended short-wavelength magnetohydrodynamic instabilities ({"}ballooning modes{"}), for the usual case with a sheared plasma flow and a magnetic shear that passes through zero near the TB. An established technique is adapted to study this situation, finding instability if (1) there is a low-pressure gradient, and if (2) the nearest {"}resonant surface{"} at which a Fourier mode is resonant, is sufficiently close. Surprisingly, flow shear is no more stabilizing than for magnetic shears of order one. This is explained. Without a strongly stabilizing mechanism, ballooning modes will fundamentally limit a TB's radial extent, preventing them from extending across the entire plasma radius.",

author = "Webster, {A J} and Szwer, {D J} and Wilson, {H R}",

year = "2005",

month = "9",

doi = "10.1063/1.2032742",

language = "English",

volume = "12",

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journal = "Physics of Plasmas",

issn = "1070-664X",

publisher = "American Institute of Physics Publising LLC",

number = "9",

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TY - JOUR

T1 - The stability of ballooning modes in tokamaks with internal transport barriers

AU - Webster, A J

AU - Szwer, D J

AU - Wilson, H R

PY - 2005/9

Y1 - 2005/9

N2 - Modern tokamaks can produce transport barriers (TBs)-localized regions with an increased energy confinement. Previous studies have been unable to examine the stability of internal TBs to radially extended short-wavelength magnetohydrodynamic instabilities ("ballooning modes"), for the usual case with a sheared plasma flow and a magnetic shear that passes through zero near the TB. An established technique is adapted to study this situation, finding instability if (1) there is a low-pressure gradient, and if (2) the nearest "resonant surface" at which a Fourier mode is resonant, is sufficiently close. Surprisingly, flow shear is no more stabilizing than for magnetic shears of order one. This is explained. Without a strongly stabilizing mechanism, ballooning modes will fundamentally limit a TB's radial extent, preventing them from extending across the entire plasma radius.

AB - Modern tokamaks can produce transport barriers (TBs)-localized regions with an increased energy confinement. Previous studies have been unable to examine the stability of internal TBs to radially extended short-wavelength magnetohydrodynamic instabilities ("ballooning modes"), for the usual case with a sheared plasma flow and a magnetic shear that passes through zero near the TB. An established technique is adapted to study this situation, finding instability if (1) there is a low-pressure gradient, and if (2) the nearest "resonant surface" at which a Fourier mode is resonant, is sufficiently close. Surprisingly, flow shear is no more stabilizing than for magnetic shears of order one. This is explained. Without a strongly stabilizing mechanism, ballooning modes will fundamentally limit a TB's radial extent, preventing them from extending across the entire plasma radius.

U2 - 10.1063/1.2032742

DO - 10.1063/1.2032742

M3 - Article

VL - 12

SP - -

JO - Physics of Plasmas

JF - Physics of Plasmas

SN - 1070-664X

IS - 9

M1 - 092502

ER -