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and disappears without any trace. Fig. (2.4) shows the effect of the

population of nonthermal ions  on the shape of the envelope DA rogue

waves. It is obvious that, the amplitude of the rogue wave decreases with
the increase of . On the other hand, the charge number of negatively

charged hot dust   plays the rule of decreasing the amplitude and the

width of the rogue wave as shown in Fig. (2.5). The change of DA

rogue wave features with the parameter   is shown in Fig. (2.6). It
is emphasized that   reduces the amplitude of the rogue wave which

confirms the result of Fig. (2.5). Furthermore, in Fig. (2.7), the increase

of the carrier wavenumber  decreases the pulses tall up to a critical value.
After this value, increasing  more leads to an increases of dispersion,

nonlinearity then concentrates a considerable energy. In summary, it has

been found that the presence of the population of nonthermal ions ,the
carrier wave number , the equilibrium density of hot dust grains  0 and

the charge number for negatively charged hot dust   modify the properties

of the dust acoustic rogue waves significantly and the results presented here
would be useful in understanding salient features of localized electrostatic

perturbations in space plasmas such as dusty plasma existing in Saturn

F-rings.

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