Constraining Flavor Changing Interactions from LHC Run-2 Dilepton Bounds with Vector Mediators

TL;DR

This paper investigates whether vector mediators can produce observable flavor-changing signals at the LHC without conflicting with dilepton resonance constraints, concluding such signals are highly constrained unless specific model textures are assumed.

Contribution

It provides a detailed analysis of the interplay between flavor-changing neutral currents and dilepton bounds within 3-3-1 models, highlighting the severe restrictions on new physics signals.

Findings

Dilepton bounds strongly constrain flavor-changing interactions in vector mediator models.

In 3-3-1 models, new physics signals are unlikely unless specific CKM textures are assumed.

Current LHC data leaves little room for observable flavor-changing signals from vector mediators.

Abstract

Within the context of vector mediators, is a new signal observed in flavor changing interactions, particularly in the neutral mesons systems $K^{0}-\bar{K}^{0}$, $D^{0}-\bar{D}^{0}$ and $B^0-\bar{B^0}$, consistent with dilepton resonance searches at the LHC? In the attempt to address this very simple question, we discuss the complementarity between flavor changing neutral current (FCNC) and dilepton resonance searches at the LHC run 2 at $13$TeV with $3.2\, {\rm fb^{-1}}$ of integrated luminosity, in the context of vector mediators at tree level. Vector mediators, are often studied in the flavor changing framework, specially in the light of the recent LHCb anomaly observed at the rare B decay. However, the existence of stringent dilepton bound severely constrains flavor changing interactions, due to restrictive limits on the $Z^{\prime}$ mass. We discuss this interplay explicitly in the well motivated framework of a 3-3-1 scheme, where fermions and scalars are arranged in the fundamental representation of the weak SU(3) gauge group. Due to the paucity of relevant parameters, we conclude dilepton data leave little room for a possible new physics signal stemming from these systems, unless a very peculiar texture parametrization is used in the diagonalization of the CKM matrix. In other words, if a signal is observed in such flavor changing interactions, it is unlikely comes from a 3-3-1 model.