$Z'$ discovery potential at the LHC in the minimal $B-L$ extension of the Standard Model

TL;DR

This paper evaluates the LHC's potential to discover a $Z'$ boson in a minimal $B-L$ extension of the Standard Model, analyzing different energies and decay channels, and proposing methods to improve sensitivity over existing experiments.

Contribution

It provides a detailed analysis of $Z'$ discovery prospects at the LHC within a minimal $B-L$ model, including novel analysis techniques and sensitivity comparisons with Tevatron results.

Findings

Electrons offer higher sensitivity than muons for small couplings.

LHC at 7 TeV can match Tevatron results for lower $Z'$ masses.

Potential to measure $Z'$ width at smaller masses with electrons.

Abstract

We present the Large Hadron Collider (LHC) discovery potential in the $Z'$ sector of a $U(1)_{B-L}$ enlarged Standard Model (that also includes three heavy Majorana neutrinos and an additional Higgs boson) for $\sqrt{s}=7$, 10 and 14 TeV centre-of-mass (CM) energies, considering both the $Z'_{B-L}\rightarrow e^+e^-$ and $Z'_{B-L}\rightarrow \mu^+\mu^-$ decay channels. The comparison of the (irreducible) backgrounds with the expected backgrounds for the D$\O$ experiment at the Tevatron validates our simulation. We propose an alternative analysis that has the potential to improve the D$\O$ sensitivity. Electrons provide a higher sensitivity to smaller couplings at small $Z'_{B-L}$ boson masses than do muons. The resolutions achievable may allow the $Z'_{B-L}$ boson width to be measured at smaller masses in the case of electrons in the final state. The run of the LHC at $\sqrt{s}=7$ TeV, assuming at most $\int \mathcal{L} \sim 1$ fb$^{-1}$, will be able to give similar results to those that will be available soon at the Tevatron in the lower mass region, and to extend them for a heavier $M_{Z'}$.