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the low-frequency ion acoustic perturbations can lead to propagation of

                   the nonlinear surface plasma rogue waves. El-Labany et al. [129] in-

                   spected the existence of rogue wave in a negative-positive ion plasmas in
                   Titan’s atmosphere. Abdelwahed and El-Shewy [130] investigated the

                   improvement of IAW shape in warm plasmas and explained the explosive

                   and rouge waves by the rational solutions of NLS equations. Furthermore,

                   many studies in astrophysics used the rational solutions of NLS equa-
                   tion that give a suitable rogue waves description [131-133]. Chawla et al.

                   [134] examined the effect of plasma parameters on the stability of mod-

                   ulation of IAWs in a collisionless (e-p-i) plasma with warm ions. They
                   found that, the instability regions are shifted according to the wavenum-

                   ber. On the other hand, El Wakil et al. [135] studied the rational solution

                   of the NLS equation equation in auroral zone plasma. El-Bedwehy and
                   Moslem [136] studied the properties of nonlinear structures of solitons

                   and shocks in magnetoplasma in the presence of electrons and positrons

                   obeying kappa distribution. Recently, Guo et al. [137] investigated rogue
                   waves in the case of unmagnetized plasma via the NLS equation. Based

                   on the dispersion and nonlinear coefficients that depend mainly on the

                   plasma parameters, the stability (instability) regions are also studied and

                   they observed rogue wave triplets in the unstable region. In this chapter,
                   DA rogue wave in collisionless unmagnetized dusty plasmas consisting of

                   electrons, nonthermal ions, hot and cold dust grains will be studied.




                   2.2        Basic Equations



                     The dusty plasma model, we are studying, is unmagnetized and consists
                   of four components: isothermal electrons, and nonthermal ions, hot and

                   cold dust species. The electrons are assumed to follow the Boltzmann




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