One effect in these objects is a shift of the center of density away from the geometric center, a shift likewise named for Shafranov.
The equation governing these systems sets the minor-radius laplacian of psi equal to the sum of terms containing the derivative of pressure in terms of psi minus a term containing the poloidal current times its derivative; that equation is the Grad-Shafranov equation. One effect in these objects is a shift of the center of density away from the geometric center, a shift likewise named for Shafranov. Confinement in these devices occurs due to a driven torodial plasma current; these devices are thus similar to stellerators, which have additional helical coils. The largest of them currently in operation is JET, which will be replaced by ITER when the latter is complete. For 10 points, name these toroidal magnetic confinement devices for hot plasmas which are candidates as nuclear fusion reactors.
The equation governing these systems sets the minor-radius laplacian of psi equal to the sum of terms containing the derivative of pressure in terms of psi minus a term containing the poloidal current times its derivative; that equation is the Grad-Shafranov equation.
 tokamaks [accept spheromaks before “JET”; prompt on fusion reactors; or plasma devices] 