A new look at the double sine-Gordon kink-antikink scattering

Abstract

We study the kink-antikink scattering within the double sine-Gordon model. In the numerical simulations we found a critical value v cr of the initial velocity v in, which separates two different scenarios: At v in < v cr the kinks capture each other and form a bound state, while at v in > v cr the kinks pass through each other and escape to infinities. We obtain non-monotonous dependence of v cr on the model parameter R. Besides that, at some initial velocities below v cr we observe formation and interaction of the so-called oscillons (new phenomenon), as well as escape windows (well-known phenomenon).