On the Ordinary mode Instability for Non-Extensive Anisotropic Distribution

The solar wind data is explained by the Bale-diagram as represented by the temperature anisotropy-plasma beta (i.e., A= T_prep/T_parallel, beta_parallel ) space. Recently a great interest is developed to explain the lower right (i.e., A<1, beta_parallel >1) and lower left bottom (i.e., A<1, beta_parallel <1) regions of Bale-diagram by the O-mode instability using Bi-Maxwellian and the counter-streaming distributions respectively. In this paper, the O-mode instability is studied by using the non-extensive anisotropic distribution which follows the Tsallis statistics. The effect of non-extensivity parameter (q) is analyzed on the maximum growth rate of O-mode instability by using the exact numerical method. The growth rates for O-mode instability in Bi-kappa distribution and Bi-Maxwellian distribution are also obtained in the limits q=1-(1/kappa) and q=1 respectively.