Constraining CPT-odd nonminimal interactions in the Electroweak sector

TL;DR

This paper explores CPT-odd, Lorentz-violating nonminimal couplings in the Electroweak sector, proposing gauge-invariant terms and deriving experimental bounds from decay rate measurements.

Contribution

It introduces new CPT-odd, Lorentz-violating nonminimal interactions in the Electroweak theory and constrains their magnitude using experimental decay data.

Findings

Upper bounds of 10^{-15} and 10^{-14} (eV)^{-1} on the nonminimal couplings

Proposed gauge-invariant CPT-odd interactions in the Electroweak sector

Reassessment of W and Z decay rates with Lorentz-violating terms

Abstract

In this work, we propose two possibilities of CPT-odd and Lorentz-violating (LV) nonminimal couplings in the Electroweak sector. These terms are gauge-invariant and couple a fixed 4-vector to the physical fields of the theory. After determining the LV contributions to the electroweak currents, we reassess the evaluation of the decay rate for the vector mediators $W$ and $Z$. Using the experimental uncertainty in these decay rates, upper bounds of $1$ part in $10^{-15}$ (eV )$^{-1}$ and $10^{-14}$ (eV )$^{-1}$ are imposed on the magnitude of the proposed nonmimal interactions.