Dust-acoustic soliton in electronegative complex plasmas with streaming positive ions

The Sagdeev potential approach is applied to investigate theoretically and numerically the dust acoustic soliton in electronegative dusty plasmas with streaming positive ions. The self-consistent dust charge variation is also taken into account. The lower and upper limits of Mach numbers are then derived. Moreover, it is found that both the positive ion streaming velocity and negative ion density can lower the two limits. The soliton profiles, involving the spatial potential, particle densities, dust surface potential, and space net charge distributions in various cases, are plotted and discussed.