Effects of the FCNC Couplings in Production of New Heavy Quarks withinZ′Models at the LHC

V Çetinkaya,O Çakır,V Arı

doi:10.1155/2016/1760219

Abstract

We study the flavor changing neutral current couplings of new heavy quarks through theZ′models at the LHC. We calculate the cross sections for the signal and the corresponding standard model background processes. Considering the present limits on the mass of new heavy quarks and theZ′boson, we performed an analysis to investigate the parameter space (mixing and mass) through differentZ′models. For FCNC mixing parameterx=0.1and theZ′massMZ′=2000 GeV and new heavy quark massmt′=700 GeV at the LHC withs=13 TeV, we find the cross section for single production of new heavy quarks associated with top quarks as5.8 fb,3.3 fb,1.5 fb, and1.2 fb within theZη′,Zψ′,ZLP′, andZχ′models, respectively. It is shown that the sensitivity would benefit from the flavor tagging.

Highlights

Addition of new heavy quarks would require the extension of the flavor mixing in charged current interactions as well as the extension of Higgs sector in the standard model (SM)
Due to the expected smallness of the mixing between the new heavy quarks and known quarks through charged current interactions, the production and decay modes can be affected by the flavor changing neutral current (FCNC) interactions
We investigate the single production of new heavy quarks via FCNC interactions through Z󸀠 boson exchange at the Large Hadron Collider (LHC)

Summary

Introduction

Addition of new heavy quarks would require the extension of the flavor mixing in charged current interactions as well as the extension of Higgs sector in the standard model (SM). A work performed in [11, 12] presents the effects of FCNC interactions induced by an additional Z󸀠 boson on the single top quark and top quark pair production at the LHC (√s = 14 TeV). Analyzing the signal observability (via contour plots) for different mass values of the Z󸀠 boson and new heavy quarks as well as the mixing parameter through FCNC interactions are another feature of the work. We analyzed the signal observability for the Z󸀠qq󸀠 FCNC interactions We consider both t󸀠t and t󸀠t single new heavy quark productions for the purpose of enriching the signal statistics even at the small couplings.

FCNC Interactions

Single Production of New Heavy Quarks

Analysis

Conclusion