Electrostatic instabilities in anti-loss-cone plasma

It is shown that both lower hybrid and modified electron acoustic instabilities can be excited in a hot anti-loss-cone plasma co-existing with a rarefied cold plasma, provided the anti-loss-cone factor, ρ, exceeds a value T_m/T_t, where T_m and T_t are the parallel temperatures of missing and trapped electrons respectively. These instabilities are excited in a bounded range of wavenumbers and the growth rates are enhanced with the increase of cold plasma density. For

T_m/T_t < ρ > (T_m/T_t)½

both the instabilities are of resonant type whereas for ρ > (T_m/T_t)½ both may be converted into non-resonant types. These instabilities are expected to give rise to the heating of protons as well as electrons in the magnetosphere beyond the plasmapause.