Backlund transformations, a simple transformation and exact solutions for dust-acoustic solitary waves in dusty plasma consisting of cold dust particles and two-temperature isothermal ions

Dusty plasma with inertial dust fluid and two-temperature ions admits both compressive and rarefactive solitary waves. The Korteweg-de Vries equations (KdV-type equations) with cubic nonlinearity at the critical density of lo w-temperature isothermal ions are considered to discuss properties of dust- acoustic solitary waves. In the vicinity of the critical density of low-tem perature ions, a KdV-type equation with mixed nonlinearity is discussed. Th e method of characteristics is used and the Backlund transformations (BTs) are employed to generate new solutions from the old ones. Another new solut ion of the KdV-mKdV equation is obtained using a simple transformation betw een the sine-Gordon equation and a linear equation combined with an extensi on of the tanh method of Malfliet. (C) 1999 American Institute of Physics. [S1070-664X(99)00904-0].