A Magnetically Confined Gas = 2

  
Figure 8: Possible paths for a charged particle near a magnetic field

A charged particle in the presence of a magnetic field line has only two degrees of freedom. It can gyrate in a circular orbit around the field line or/and it can move along the field line. Typically, one has of energy per degree of freedom, this implies that the internal energy, u, of such a magnetic gas is simply

where n is the number density of the plasma, is Boltzmann's constant and T is the temperature in Kelvin. For a classical ideal gas, the pressure, p, of the gas is

So, is equal to 2.

© Copyright Astronomical Society of Australia 1997