Ion-Acoustic Density Hump Solitons in (r,q) Distributed Plasmas using Python
Keywords:
Non-Maxwellian Distribution, (r,q) Distribution, Electrostatic Solitary Waves, Solitons, Flat-Topped Distribution, Ion-Acoustic WavesAbstract
Electron Velocity Distributions (EVDs) with a flat top at low energy and/or an enhanced tail at high energies are commonly observed in Earth's magnetosphere and solar wind. Noteworthy is the fact that only generalized distribution with two spectral indices fit such observed flat top distributions, since at low energies neither kappa nor Maxwellian distribution can fit the observed EVDs. In the limiting cases, and ; distribution reduces the Maxwellian and kappa distributions, respectively. In the current fluid model, for the first time, electrons are treated as distributed and Sagdeev potential is derived for fully nonlinear fluid equations for ion-acoustic waves and obtained density humps to interpret the observations. We analyzed the properties of solitary structures using observed plasma parameters and values of and indices that matched the reported values. We found that flat top distribution supports the density hump solitons with larger amplitude.
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