Distinguishing Flavor Non-universal Colorons from Z' Bosons at the LHC

TL;DR

This paper extends a method to distinguish between coloron and Z' boson resonances at the LHC, especially when their couplings are flavor non-universal, by incorporating heavy-flavor decay measurements.

Contribution

It introduces a model-independent approach to differentiate colorons from Z' bosons with flavor non-universal couplings using heavy-flavor decay data.

Findings

Heavy-flavor decay measurements enable conclusive identification of vector bosons.

The method is applicable for a wide range of resonance masses and couplings.

Measurements can distinguish colorons from Z' bosons even with non-Standard invisible decays.

Abstract

Electrically-neutral massive color-singlet and color-octet vector bosons, which are often predicted in Beyond the Standard Model theories, have the potential to be discovered as dijet resonances at the LHC. A color-singlet resonance that has leptophobic couplings needs further investigation to be distinguished from a color-octet one. In previous work, we introduced a method for discriminating between the two kinds of resonances when their couplings are flavor-universal, using measurements of the dijet resonance mass, total decay width and production cross-section. Here, we describe an extension of that method to cover a more general scenario, in which the vector resonances could have flavor non-universal couplings; essentially, we incorporate measurements of the heavy-flavor decays of the resonance into the method. We present our analysis in a model-independent manner for a dijet resonance with mass 2.5-6.0 TeV at the LHC with $\sqrt{s}=14$ TeV and integrated luminosities 30, 100, 300 and 1000 ${\rm fb}^{-1}$, and show that the measurements of the heavy-flavor decays should allow conclusive identification of the vector boson. Note that our method is generally applicable even for a Z' boson with non-Standard invisible decays. We include an appendix of results for various resonance couplings and masses to illustrate how well each observable must be measured to distinguish colorons from Z' bosons.