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arXiv · 2512.07893

Kinetic Alfv\'en waves in the temperature anisotropic space plasma with a kappa-Maxwellian distribution

Rui Huo·Jiulin Du·Ran Guo
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Abstract

The dispersion and damping rate of kinetic Alfv\'en waves are studied in temperature anisotropic space plasma with kappa-Maxwellian distribution. Employing a kinetic approach, the wave frequency and damping rate of kinetic Alfv\'en waves and the modified ion acoustic waves are derived in a low \b{eta} plasma, which both depend on the parameters \k{appa} and . The numerical analyses show that the wave frequency of kinetic Alfv\'en waves is larger in kappa-Maxwellian plasma than that in Maxwellian case. The wave frequency of the modified ion acoustic waves in kappa-Maxwellian plasma is larger in the short-wave region but smaller in the long-wave region than that in Maxwellian case. Again, we found that the damping rate of kinetic Alfv\'en waves in kappa-Maxwellian plasma is stronger than that in Maxwellian case. The damping rate of modified ion acoustic waves in kappa-Maxwellian plasma is stronger in the short-wave region but weaker in the long-wave region than that in Maxwellian case. The impact of the parameter on the two modes is relatively small because we consider the low \b{eta} case. These results are helpful for us to understand better the characteristics of kinetic Alfv\'en waves in space plasma.

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BibTeXRIS

Rui Huo, Jiulin Du, Ran Guo. 2025-12-04. Kinetic Alfv\'en waves in the temperature anisotropic space plasma with a kappa-Maxwellian distribution. https://arxiv.org/abs/2512.07893

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