Large amplitude electrostatic solitary structures in a hot non-thermal dusty plasma

A rigorous theoretical investigation has been made of large amplitude compressive and rarefactive dust-acoustic solitary waves in an unmagnetized hot dusty plasma consisting of a negatively charged hot dust fluid and non-thermally distributed ions. The pseudo-potential approach, which is valid for arbitrary amplitude solitary waves, has been employed. It is shown that the presence of the fast or non-thermal ions may allow compressive and rarefactive solitary waves to coexist. It is found that the effect of the dust fluid temperature changes the minimum values of alpha (a parameter determining the number of fast ions present in our dusty plasma model) and M (the Mach number) for which the compressive and rarefactive solitary waves can coexist. It is also observed that as the dust fluid temperature rises, the amplitude of both the compressive and rarefactive solitary waves decrease, whereas their width increases. The implications of these results to some space and astrophysical dusty plasma situations are briefly discussed. (C) 2000 Elsevier Science Ltd. All rights reserved.