Search for Higgs boson decays into a $Z$ boson and a light hadronically decaying resonance using 13 TeV $pp$ collision data from the ATLAS detector

Abstract

A search for Higgs boson decays into a $Z$ boson and a light resonance in two-lepton plus jet events is performed, using a $pp$ collision dataset with an integrated luminosity of 139 fb${}^{-1}$ collected at $\sqrt{s}=13$ TeV by the ATLAS experiment at the CERN LHC. The resonance considered is a light boson with a mass below 4 GeV from a possible extended scalar sector, or a charmonium state. Multivariate discriminants are used for the event selection and for evaluating the mass of the light resonance. No excess of events above the expected background is found. Observed (expected) 95$\%$ confidence-level upper limits are set on the Higgs boson production cross section times branching fraction to a $Z$ boson and the signal resonance, with values in the range 17 pb to 340 pb ($16_{-5}^{+6}$ pb to $320_{-90}^{+130}$ pb) for the different light spin-0 boson mass and branching fraction hypotheses, and with values of 110 pb and 100 pb ($100_{-30}^{+40}$ pb and $100_{-30}^{+40}$ pb) for the ${\eta }_c$ and $J/\psi$ hypotheses, respectively.

32 pages in total, author list starting page 16, 2 figures, 1 table, published in Phys. Rev. Lett. All figures including auxiliary figures will be available at https://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/HDBS-2018-37

References in corpus (17)

• Observation of a new particle in the search for the Standard Model Higgs boson with the ATLAS detector at the LHC
• Observation of a new boson at a mass of 125 GeV with the CMS experiment at the LHC
• Parton distributions for the LHC
• Matching NLO QCD computations with Parton Shower simulations: the POWHEG method
• New parton distributions for collider physics
• Event generation with SHERPA 1.1
• Combined Measurement of the Higgs Boson Mass in $pp$ Collisions at $\sqrt{s}=7$ and 8 TeV with the ATLAS and CMS Experiments
• Pileup subtraction using jet areas
• Collider Probes of Axion-Like Particles
• Measurement of the $Z/{\gamma }^{\ast }$ boson transverse momentum distribution in $pp$ collisions at $\sqrt{s}$ = 7 TeV with the ATLAS detector
• Measurement of the muon reconstruction performance of the ATLAS detector using 2011 and 2012 LHC proton-proton collision data
• New Angles on Energy Correlation Functions
• Higgs-dependent Yukawa couplings
• An Exclusive Window onto Higgs Yukawa Couplings
• Search for a standard model-like Higgs boson in the mu+ mu- and e+ e- decay channels at the LHC
• LHC discovery potential of the lightest NMSSM Higgs in the h1 -> a1 a1 -> 4 muons channel
• A Two Higgs Doublet Model for Dark Matter and Neutrino Masses

Cited by in corpus (16)

• Feebly-Interacting Particles:FIPs 2020 Workshop Report
• ABCDisCo: Automating the ABCD Method with Machine Learning
• Supervised Jet Clustering with Graph Neural Networks for Lorentz Boosted Bosons
• Axion-like particles as mediators for dark matter: beyond freeze-out
• Exotic Higgs Decays
• Search for low-mass dilepton resonances in Higgs boson decays to four-lepton final states in proton-proton collisions at $\sqrt{s}=$ 13 TeV
• Prospects for quarkonium studies at the high-luminosity LHC
• Non-Parametric Data-Driven Background Modelling using Conditional Probabilities
• Search for decays of the 125 GeV Higgs boson into a Z boson and a $\rho$ or $\varphi$ meson
• Meta-learning and data augmentation for mass-generalised jet taggers
• Semi-dark Higgs decays: sweeping the Higgs neutrino floor
• Same-Sign Taus Signatures of Maximally Flavor-Violating Scalars at the LHC
• Improving smuon searches with Neural Networks
• Preserving New Physics while Simultaneously Unfolding All Observables
• Collider phenomenology of new neutral scalars in a flavoured multi-Higgs model
• Jets and Photons Spectroscopy of Higgs-ALP Interactions