DRIFT MODES IN A MAGNETIC QUADRUPOLE

We consider intermediate frequency electrostatic drift modes in the UM IST magnetic quadrupole, with one and two full wavelengths along a clo sed magnetic field line. The dispersion curves and the shape of the lo ngitudinal eigenfunctions are calculated. The effect of variations of various parameters is also studied. In particular, we conclude that wh ereas resonant non-linear interactions between the drift modes are pos sible for some parameter values, the interaction may be strongly non-r esonant for other parameter values.