A composite Heavy Vector Triplet in the ATLAS di-boson excess

TL;DR

This paper explores whether a composite heavy vector triplet, predicted by natural new physics models, can explain the ATLAS di-boson excess without conflicting with other resonance search results.

Contribution

It assesses the compatibility of a composite vector triplet with the ATLAS excess and other resonance constraints, highlighting its potential as a plausible new particle signal.

Findings

The hypothesis is not excluded by current searches.

Predicted signals are near the sensitivity of multiple channels.

Some channels show fluctuations close to observed limits.

Abstract

Composite vector resonances in the triplet of the SM SU$(2)_{L}$ gauge group are a universal prediction of "natural" new physics models involving a new strongly-interacting sector and are therefore among the most plausible new particles that the LHC could discover. We consider the possibility that one such triplet could account for the ATLAS excess in the invariant-mass spectrum of boson-tagged jets and we assess the compatibility of this hypothesis with all other relevant resonance searches. We find that the hypothesis is not excluded and that the predicted signal is close to the expected sensitivity of several channels, some of which show an upper fluctuation of the observed limit while others do not. An accurate study of the signal compatibility with these fluctuations could only be performed by the ATLAS and CMS collaborations.