Mirror instability with electron temperature effects

Linear kinetic mirror instabilities of a homogeneous magnetized plasma in w hich both ions and electrons have the bi-Maxwellian distributions are inves tigated in the low-frequency and long-wavelength limit. It is shown that, i n contrast to the case of cold electrons, the criterion for the mirror inst ability has an upper limit, above which the mirror mode becomes oscillating one. This can possibly account for the oscillatory variations of observed mirror waves in the space plasma. In addition it is also shown that the gro wth rate of the nonpropagation mirror mode increases rapidly with the aniso tropy parameter and is slightly higher than its value under the cold electr on assumption, but that the oscillating mirror mode remains nearly a consta nt growth rate.