Unique Signatures of Unparticle Resonances at the LHC

TL;DR

This paper investigates the unique resonance signatures of unparticles at the LHC, focusing on their distinguishability from conventional Z' resonances, considering the effects of conformal symmetry breaking and decay widths.

Contribution

It introduces the distinctive shape of unparticle resonances in high-energy collisions and assesses their detectability and differentiation from standard resonances at the LHC.

Findings

Unparticle resonances have non-Breit-Wigner shapes due to conformal symmetry breaking.

Distinguishing unparticle resonances from Z'-like structures is challenging at high luminosities.

High luminosity may not suffice to differentiate these resonances for many model parameters.

Abstract

The coupling of unparticles to the Standard Model (SM) Higgs boson leads to a breaking of conformal symmetry which produces an effective mass term in the unparticle propagator. Simultaneously, the unparticle couplings to other SM fields produces an effective unparticle decay width via one-loop self-energy graphs. The resulting unparticle propagator then leads to a rather unique appearance for the shape of unparticle resonances that are not of the usual Breit-Wigner variety when they form in high energy collisions. In this paper we explore whether or not such resonances, appearing in the Drell-Yan channel at the LHC, can be differentiated from more conventional $Z'$-like structures which are representative of the typical Breit-Wigner lineshape. We will demonstrate that even with the high integrated luminosities available at the LHC it may be difficult to differentiate these two types of resonance structures for a substantial range of the unparticle model parameters.