Search for Higgs and Z boson decays to J/ψ or Y pairs in the four-muon final state in proton-proton collisions at s=13TeV
Journal
Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics
Journal Volume
797
Date Issued
2019
Author(s)
Sirunyan A.M. et al.
Tumasyan, A.
Adam, W.
Ambrogi, F.
Bergauer, T.
Brandstetter, J.
Dragicevic, M.
Erö, J.
Escalante Del Valle, A.
Flechl, M.
Frühwirth, R.
Jeitler, M.
Krammer, N.
Krätschmer, I.
Liko, D.
Madlener, T.
Mikulec, I.
Rad, N.
Schieck, J.
Schöfbeck, R.
Spanring, M.
Abstract
A search for decays of the Higgs and Z boson to pairs of J/ψ or Y(nS) (n = 1, 2, 3) mesons, with their subsequent decay to μ+μ? pairs, is presented. The analysis uses data from proton-proton collisions at s=13TeV, collected with the CMS detector at the LHC in 2017 and corresponding to an integrated luminosity of 37.5fb?1. While an observation of such a decay with this sample would indicate the presence of physics beyond the standard model, no significant excess is observed. Upper limits at 95% confidence level are placed on the branching fractions of these decays. In the J/ψ pair channel, the limits are 1.8×10?3 and 2.2×10?6 for the Higgs and Z boson, respectively, while in the combined Y(nS) pair channel, the limits are 1.4×10?3 and 1.5×10?6, respectively, when the mesons from the Higgs and Z boson decay are assumed to be unpolarized. When fully longitudinal and transverse polarizations are considered the limits reduce by about 22–29% and increase by about 10–13%, respectively. ? 2019 The Author(s)
Type
journal article