Obliquely propagating dust-acoustic solitary waves in a magnetized dusty plasma

A theoretical investigation has been made of obliquely propagating dust-acoustic solitary waves in a magnetized dusty plasma which consists of a negatively charged cold dust fluid, Boltzmann-distributed electrons, and nonthermally distributed ions. The reductive perturbation method has been employed to derive the Kortewegde Vries (K-dV) equation which admits a solitary wave solution for small but finite amplitude limit. The solitary wave may change from compressive to rarefactive depending on the value of alpha (a parameter determining the number of nonthermal ions present in this plasma model). It is seen that for no background free electron there exist compressive (rarefactive) solitary waves when alpha less than or equal to (>)0.155 and that, as the number of the background free electrons increases, we need a higher value of alpha in order for rarefactve solitary waves to exist. The effects of obliqueness and external magnetic field on the nature of these compressive and rarefactive solitary waves are also discussed.