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arXiv · 1805.07017

Kink scattering in a hybrid model

D. Bazeia·Adalto R. Gomes·K. Z. Nobrega·Fabiano C. Simas
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Abstract

In this work we consider a model where the potential has two topological sectors connecting three adjacent minima, as occurs with the $ϕ^6$ model. In each topological sector, the potential is symmetric around the local maximum. For $ϕ>0$ there is a linear map between the model and the $λϕ^4$ model. For $ϕ<0$ the potential is reflected. Linear stability analysis of kink and antikink lead to discrete and continuum modes related by a linear coordinate transformation to those known analytically for the $λϕ^4$ model. Fixing one topological sector, the structure of antikink-kink scattering is related to the observed in the $λϕ^4$ model. For kink-antikink collisions a new structure of bounce windows appear. Depending on the initial velocity, one can have oscillations of the scalar field at the center of mass even for one bounce, or a change of topological sector. We also found a structure of one-bounce, with secondary windows corresponding to the changing of the topological sector accumulating close to each one-bounce windows. The kink-kink collisions are characterized by a repulsive interaction and there is no possibility of forming a bound state.

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D. Bazeia, Adalto R. Gomes, K. Z. Nobrega, Fabiano C. Simas. 2019-05-01. Kink scattering in a hybrid model. https://doi.org/10.1016/j.physletb.2019.04.013

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