Effects of a CPT-even and Lorentz-violating nonminimal coupling on the electron-positron scattering

TL;DR

This paper introduces a new CPT-even, Lorentz-violating nonminimal coupling in the standard model extension and investigates its effects on electron-positron scattering, setting stringent experimental bounds on the coupling parameters.

Contribution

It proposes a novel CPT-even, Lorentz-violating nonminimal coupling involving the tensor $(K_{F})_{ ext{μν αβ}}$ and analyzes its impact on scattering cross sections.

Findings

Upper bounds of 10^{-12} (eV)^{-1} on Lorentz-violating parameters

Constraints derived from electron-positron scattering data

Analysis focused on parity-even and parity-odd components

Abstract

We propose a new \emph{CPT}-even and Lorentz-violating nonminimal coupling between fermions and Abelian gauge fields involving the CPT-even tensor $(K_{F})_{\mu\nu\alpha\beta}$ of the standard model extension. We thus investigate its effects on the cross section of the electron-positron scattering by analyzing the process $e^{+}+e^{-}\rightarrow\mu^{+}+\mu^{-}$. Such a study was performed for the parity-odd and parity-even nonbirefringent components of the Lorentz-violating $(K_{F})_{\mu\nu\alpha\beta}$ tensor. Finally, by using experimental data available in the literature, we have imposed upper bounds as tight as $10^{-12}(eV)^{-1}$ on the magnitude of the CPT-even and Lorentz-violating parameters while nonminimally coupled.