Finite-beta and curvature drift effects on drift waves near the plasmapause

The linear stability of finite-#betta# drift waves, near the plasmapause of the earth, is analysed for the case in which the magnetic field is non-uniform in two dimensions. The coupling of the driftwave to the oscillation of the magnetic field, due to non-zero #betta#, is found to be destabilizing. The spatial structure of the unstable mode is found to be governed by the 'curvature' scale length of the equilibrium magnetic field. (author)