Modulational instability and bright envelope solitons of ion acoustic waves in dense plasma consisting of ultra-relativistic degenerate electrons and positrons, cold and mobile inertial ions, and negatively charged static dust particles have been investigated using Fried and Ichikawa method. Nonlinear Schrodinger equation has been derived and the growth rate of modulationally unstable ion acoustic wave in such plasma is discussed. It has been found that ion acoustic wave will be always modulationally unstable for all possible values of density of positrons, electrons and charged dust particle but there is no instability of the wave for any value of plasma parameters in such plasma. The solutions of ion acoustic envelope- solitons and rogue waves are obtained from the Nonlinear Schrodinger equation. The theoretical results have been analyzed numerically for different values of plasma parameters and the results are presented graphically. It is found that only bright envelope soliton would be excited in the ultra-relativistic plasma. Our results are new and may be applicable for the study of nonlinear wave processes in relativistic degenerate dense plasmas of astrophysical objects, namely, in white dwarfs and neutron stars.

中文翻译：

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超相对论简并的致密电子离子-正电子等离子体中亮包络孤子和流氓波的调制不稳定性

使用Fried and Ichikawa方法研究了由超相对论性简并电子和正电子，冷态和移动性惯性离子以及带负电的静态尘埃粒子组成的稠密等离子体中离子声波的调制不稳定性和明亮包络孤子。推导了非线性薛定inger方程，并讨论了这种等离子体中调制不稳定离子声波的增长率。已经发现，对于正电子，电子和带电尘埃密度的所有可能值，离子声波将总是调制不稳定的，但是对于这种等离子体中的任何等离子体参数值，该波都不会不稳定。离子声学包络孤子和无赖波的解是从非线性薛定inger方程获得的。对不同血浆参数值的理论结果进行了数值分析，并以图形方式显示了结果。发现在超相对论等离子体中只有明亮的包络孤子会被激发。我们的研究结果是新的，可能适用于研究相对论简并的天体物理退化等离子体中，即白矮星和中子星中的非线性波过程。