Influence of trapped electrons on the nonstationary stage of dust-ion-acoustic solitons formation from a localized perturbation

摘要

The influence of electron trapping on the evolution of a localized perturbation and its disintegration into dust-ion-acoustic solitons is studied. This paper is a theoretical attempt to extend the experimental soliton excitation of (Nakamura Y et al 2001 Phys. Plasmas 8 3921) to the case that the effect of electron trapping is considerable. We consider the situation under which the dissipative effects associated with the dust charge fluctuations and collisional processes are negligible. For this purpose, we assume an unbounded plasma composed of cold positively charged ions, cold negatively charged dusts and hot electrons. Electron trapping is included in the model as a result of nonlinear resonant interaction of the localized perturbation with electrons. A Gaussian initial perturbation is used to model the localized perturbation. The dependence of the evolution rate and the resulting solitons amplitudes and velocities on the trapping parameter, the charge state of ions and the charge density of dusts are investigated.