Effects of the Dust Charge Fluctuation and Ion Temperature on Large Amplitude Ion-acoustic Waves in a Dusty Plasma

The effects of the dust charge fluctuation and ion temperature on large amplitude ion-acoustic waves are investigated in a plasma with a finite population of negatively charged dust particles, by numerical calculation. The nonlinear structures of ion-acoustic waves are examined, showing that the conditions for existence sensitively depend on the effects of the variable charge of dust grains and ion temperature, electrostatic potential and Mach number. The electrostatic potential on the surface of dust grain particles increases the dust charge number. The effect of the ion temperature increases the propagation speed of the ion-acoustic wave, and decreases the dust charge number. It is found that both compressive and rarefactive solitons can propagate in this system and the criterion for both solitons depends on the ion temperature. The region for existence of large amplitude ion-acoustic waves significantly depends on the dust charging. New findings of large amplitude ion-acoustic waves with variable charge dust grains and finite ion temperature in a dusty plasma are predicted.