Effect of obliqueness and external magnetic field on the characteristics of dust acoustic solitary waves in dusty plasma with two-temperature nonthermal ions

In this paper, a theoretical investigation hasbeen made of obliquely propagating dust acoustic solitarywave (DASW) structures in a cold magnetized dustyplasma consisting of a negatively charged dust fluid,electrons, and two different types of nonthermal ions. TheZakharov–Kuznetsov (ZK) and modified Zakharov–Kuznetsov(MZK) equations, describing the small but finiteamplitude DASWs, are derived using a reductive perturbationmethod. The combined effects of the externalmagnetic field, obliqueness (i.e. the propagation angle),and the presence of second component of nonthermal ions,which are found to significantly modify the basic features(viz. amplitude, width, polarity) of DASWs, are explicitlyexamined. The results show that the external magneticfield, the propagation angle, and the second component ofnonthermal ions have strong effects on the properties ofdust acoustic solitary structures. The solitary waves maybecome associated with either positive potential or negativepotential in this model. As the angle between the directionof external magnetic field and the propagationdirection of solitary wave increases, the amplitude of thesolitary wave (for both positive potential and negativepotential) increases. With changing this angle, the width ofsolitary wave shows a maximum. The magnitude of theexternal magnetic field has no direct effect on the solitarywave amplitude. However, with decreasing the strength ofmagnetic field, the width of DASW increases.