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arXiv · 2107.04927

Lorentz-symmetry violation in the electroweak sector: scattering processes in future $e^+ \, e^-$ colliders

P. De Fabritiis·P. C. Malta·M. J. Neves
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Abstract

We study CPT-odd non-minimal Lorentz-symmetry violating couplings in the electroweak sector modifying the interactions between leptons, gauge mediators and the Higgs boson. The tree-level (differential) cross sections for three important electroweak processes are discussed: $e^+ \, e^- \rightarrow Z \, H$, $e^+ \, e^- \rightarrow Z \, Z$ and $\gamma \, \gamma \rightarrow W^+ \, W^-$. By considering next-generation $e^+ \, e^-$ colliders reaching center-of-mass energies at the TeV scale and the estimated improved precision for the measurements of the respective cross sections, we are able to project upper bounds on the purely time-like background 4-vector as strict as $\lesssim 10^{-5} \, \mbox{GeV}^{-1}$, in agreement with previous work on similar Lorentz-violating couplings.

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P. De Fabritiis, P. C. Malta, M. J. Neves. 2021-07-10. Lorentz-symmetry violation in the electroweak sector: scattering processes in future $e^+ \, e^-$ colliders. https://doi.org/10.1016/j.nuclphysb.2021.115628

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