Flux surface: Difference between revisions

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:<math>\psi = \int_{S_p}{\vec B \cdot \vec n dS}</math>
:<math>\psi = \int_{S_p}{\vec B \cdot \vec n dS}</math>


where ''S<sub>p</sub>'' is a ring-shaped ribbon stretched between the magnetic axis and the flux surface ''f'', and the toroidal flux by
where ''S<sub>p</sub>'' is a ring-shaped ribbon stretched between the magnetic axis and the flux surface ''f''.
(Alternatively, ''S<sub>p</sub>'' can be taken to be a horizontal surface spanning the central hole of the torus.<ref>[http://link.aps.org/doi/10.1103/RevModPhys.76.1071 A.H. Boozer, ''Physics of magnetically confined plasmas'', Rev. Mod. Phys. '''76''' (2005) 1071 - 1141]</ref>)
Likewise, the toroidal flux is defined by


:<math>\phi = \int_{S_t}{\vec B \cdot \vec n dS}</math>
:<math>\phi = \int_{S_t}{\vec B \cdot \vec n dS}</math>