Head-on Collision of Ion-acoustic Multi-Solitons in e-p-i Plasma

Abstract

The propagation and interaction between ion acoustic multi-solitons in an unmagnetized multicomponent plasma consisting of fluid hot ions, positrons and both hot and cold electrons, are investigated by employing the extended Poincare–Lighthill–Kuo (PLK) method. Two different Kortewege-de Vries (K-dV) equations are derived. The Hirota's method is applied to get the K-dV multi-solitons solution. The phase shift due to the overtaking and head- on collision of the multi-solitons is obtained.

Overtaking collisions of oblique isothermal ion‐acoustic multisolitons in ultra‐relativistic degenerate dense magnetoplasmas

“…are, respectively, the amplitudes and the phase shifts of two single OIIASs due to the overtaking collisions. Furthermore, Equation (38) indicates that we are dealing with two single OIIASs moving in the same direction. Besides, we can use the same strategy to examine the overtaking collision between the three-OIIAS solution.…”

“…where For t >> 1, the solution is asymptotically reduced to a superposition of the three single-OIIAS solutions as [26,27,38,48]…”

“…Obviously, from Equation (40), we are dealing with three single OIIASs, each of them moving in the same direction. Moreover, k 1 , k 2 , and k 2 are the wavenumbers, which define the amplitude and polarity of the two and the three OIIASs in Equations (38) and (40), respectively, and in the linear dispersion relation.…”

“…For t > > 1, the solution is asymptotically reduced to a superposition of the three single‐OIIAS solutions as [ 26,27,38,48 ] where are the amplitudes, and Γ 1 = ± (2B 1/3 /k 1 )ln|φ 123 /φ 23 |, Γ 2 = ± (2B 1/3 /k 2 )ln|φ 123 /φ 31 |, and Γ 3 = ± (2B 1/3 /k 3 )ln|φ 123 /φ 12 | are the phase shifts due to the overtaking collisions of three single OIIASs. Obviously, from Equation (40), we are dealing with three single OIIASs, each of them moving in the same direction.…”

“…They found that the larger soliton moves faster and approaches the smaller ones, and after the overtaking collision, both resume their original shape and speed. Roy et al [ 38 ] obtained the phase shift due to the overtaking collision of ion‐acoustic multisolitons. They showed that the phase shift slightly decreases as the positron‐to‐electron density ratio increases.…”