The linear waves that propagate in a two fluid magnetised plasma allowing for a non-gyrotropic perturbed ion pressure tensor are investigated. For perpendicular propagation and perturbed fluid velocity a low frequency (magnetosonic) and a high frequency (ion Bernstein) branch are identified and discussed. For both branches a comparison is made with the results of a truncated Vlasov treatment. For the low frequency branch we show that a consistent expansion procedure allows us to recover the correct expression of the finite Larmor radius corrections to the magnetosonic dispersion relation.
非回旋各向异性扰动离子压力张量下双流体磁化等离子体中传播的线性波被研究。对于垂直传播和扰动流体速度，识别并讨论了低频（磁声）分支和高频（离子伯恩斯坦）分支。对两个分支，均与截断的弗拉索夫处理结果进行了比较。对于低频分支，我们表明一致的展开过程能够恢复磁声色散关系中有限拉莫尔半径修正的正确表达式。