The rippling instability

The rippling instability of current carrying magnetically confined plasmas is investigated. Complete parallel electron dynamics, including the effects of parallel thermal conduction, compressibility, and thermal forces, is incorporated into the theory. The rippling instability is found to be purely growing at very low temperatures, propagates at the drift frequency for slightly higher temperatures, and is stabilized by parallel thermal conduction as the temperature increases further. An analytic expression for the stability criterion is given. The analytic theory agrees well with a numerical calculation.