Revealing timid pseudo-scalars with taus at the LHC

Abstract

A light pseudo-scalar that is copiously produced at the LHC may still be allowed by present searches. While masses above 65 GeV are effectively covered by di-photon searches, the lower mass window can be tested by a new search for boosted di-tau resonances. We test this strategy on a set of composite Higgs models with top partial compositeness, where most models can be probed with an integrated luminosity below 300 fb${}^{-1}$.

Comments: 5 pages, 4 figures, 2 tables. Additional material starting at page 6 after the reference list. v2: References added, typos fixed, comparison of di-tau and di-photon projected reach included in additional material. v3: discussion of systematic uncertainties and lepton isolation criteria expanded, figure 3 added, version agrees with published article