What Causes Equilibrium in an Imploding Z-Pinch?

[bman!!]

"An imploding Z-pinch is comprised of a thin-walled hollow cylinder of plasma with very low
resistivity. A constant axial current of 1MA is applied to the plasma and it starts to implode. An
additional axial field of 1 Tesla is also generated which exists only on the inside of the cylinder.
The cylinder stops imploding when which three pressures are all equal ? Why is there no
magnetic tension force involved ? If the initial radius of the cylinder is 1cm, what is its final
radius and what is the final value of Bz ?"

normally equilibrium is when the magnetic pressure due to the toroidal field pressure is equal to the thermal pressure gradient (i.e. the magnetic field causes the zpinch to contract until the compressional heating results in thermal pressure pushing outwards to counteract this effect)

however i seem to get the impression from the answers that the total equilibrium is due to the thermal pressure AND the internal (Bz) magnetic field pressure counteracting the inwards force.

or can i just calculate when the fields are equal using flux surface conservation? is so why (i think this is what my instructor shows me in the answers...)

cheers

 

[BigJDubs]

The three pressures that are all equal in this scenario are the thermal pressure gradient, the internal axial magnetic field pressure, and the external axial magnetic field pressure. There is no magnetic tension force involved because the axial field is constant and does not change over time. The final radius of the cylinder would be determined by the balance between the thermal pressure and the axial magnetic field pressure, and the final value of Bz can be calculated from the flux surface conservation equation.