Soliton, breather and double-layer structures formation of ion acoustic waves in weakly magnetized non-thermal plasmas

Abstract The dynamics of the obliquely propagating weakly nonlinear ion acoustic waves are investigated in a collisionless weakly magnetized plasmas in the context of the Cairns distributed non-thermal electrons. A three-dimensional Korteweg de-Vries (KdV) equation, colloquially known as the Laedke-Spatschek (LS) equation, has been shown to describe the dynamics of the nonlinear wave. Analytical solutions depending on the physical parameters predict solitary, periodic and breather like structures. Interestingly, at a critical value of the non-thermal parameter, the dynamics is found to be governed by a modified LS equation which is conditionally Painlevé integrable. Exact analytical solution with the help of Bäcklund transformation reveals that the modified LS equation supports a double-layer, sawtooth-like periodic and breather-like structures. The results are discussed in the context of astrophysical observations in the auroral region.