Solve the following problem from the book "Introduction to Plasma Physics / Robert J. Goldston and Paul H. Rutherford.":
PLASMA
Bo
VACUUM
Figure 9.3. A plasma equilibrium in which a uniform plasma fills all space except for an evacuated cylindrical hole produced by a current-carrying conductor (see Problem 9.1).
Problem 9.1: A plasma of uniform pressure p fills all of space except for an evacuated infinitely long cylindrical hole of radius a, which is produced by a conductor carrying a current I placed on the axis of the cylindrical hole. The conductor produces an azimuthal field Be, as shown in Figure 9.3. Show that the maximum radius of the vacuum hole that can be created in equilibrium in this way is given by a^2 = o^2/8Ï€^2p. Is there a z-directed current in the plasma? What is its magnitude and where is it located?