Co-existence of compressive and rarefactive dust acoustic solitary structures in Saturn’s rings with non-Maxwellian ions and electrons

Abstract In the present study, we investigated the existence of arbitrary amplitude dust acoustic solitons by considering the Cairns distributed ions, negatively charged streaming dust grains along with ( r, q ) distributed electrons in an un-magnetized dusty plasma. We used the pseudopotential technique to obtain the solitary wave solution. It is seen that the coexistence of rarefactive and compressive solitons is possible when ions and electrons are nonthermally distributed. We found that the soliton characteristics are strongly dependent on the choice of velocity distribution function through the nonthermal spectral indices <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mi>r</mml:mi> <mml:mo>,</mml:mo> <mml:mi mathvariant="italic">q</mml:mi> </mml:math> , <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mi>α</mml:mi> </mml:math> as well as on the ion and dust temperatures. For ( r, q ) distributed electrons, we found that the soliton amplitude increases (decreases) with smaller (higher) values of negative (positive) <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mi>r</mml:mi> </mml:math> . For Cairns distributed ions, we found a transition from negative to positive polarity solitary structures with the coexistence in between as the nonthermal parameter <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mi>α</mml:mi> </mml:math> increases. Our results gave a better explanation for the formation of dust acoustic solitary structures and their dependence on high and low energy particles in nonthermal distribution profiles in space environments.