{"@context":"http://schema.org","@id":"https://doi.org/10.17182/hepdata.153859.v2","@reverse":{"isBasedOn":[{"@type":"ScholarlyArticle","identifier":{"@type":"PropertyValue","propertyID":"URL","value":"https://inspirehep.net/literature/2851948"}},{"@id":"https://doi.org/10.1016/j.physletb.2025.139671","@type":"JournalArticle"}]},"@type":"Dataset","additionalType":"Collection","author":{"@type":"Organization","name":"ATLAS Collaboration"},"creator":{"@type":"Organization","name":"ATLAS Collaboration"},"datePublished":"2025","description":"A search for decays of the Higgs boson into a $Z$ boson and a light resonance, with a mass of 0.5-4 GeV, is performed using the full 140 fb$^{-1}$ dataset of 13 TeV proton-proton collisions recorded by the ATLAS detector during Run 2 of the LHC. Leptonic decays of the $Z$ boson and hadronic decays of the light resonance are considered. The resonance can be interpreted as a $J/\\psi$ or $\\eta_c$ meson, an axion-like particle, or a light pseudoscalar in two-Higgs-doublet models. Due to its low mass, it would be produced with high boost and reconstructed as a single small-radius jet of hadrons. A neural network is used to correct the Monte Carlo simulation of the background in a data-driven way. Two additional neural networks are used to distinguish signal from background. A binned profile-likelihood fit is performed on the final-state invariant mass distribution. Since no significant excess of events relative to the expected background is observed, 95% CL upper limits are set on the Higgs boson's branching fraction to a $Z$ boson and a light resonance.","hasPart":[{"@id":"https://doi.org/10.17182/hepdata.153859.v2/t1","@type":"Dataset","description":"The angularity, for data, background (pre- and post-reweighting) and three $H\\rightarrow Za$ signal hypotheses (for $a\\rightarrow q\\bar{q}/gg$ inclusively). Events are...","name":"Angularity distribution"},{"@id":"https://doi.org/10.17182/hepdata.153859.v2/t2","@type":"Dataset","description":"The modified energy correlation function, for data, background (pre- and post-reweighting) and three $H\\rightarrow Za$ signal hypotheses (for $a\\rightarrow q\\bar{q}/gg$...","name":"Modified energy correlation function"},{"@id":"https://doi.org/10.17182/hepdata.153859.v2/t3","@type":"Dataset","description":"$Z$ boson transverse momentum, for data, background (pre- and post-reweighting) and three $H\\rightarrow Za$ signal hypotheses (for $a\\rightarrow q\\bar{q}/gg$ inclusively)....","name":"Z boson transverse momentum"},{"@id":"https://doi.org/10.17182/hepdata.153859.v2/t4","@type":"Dataset","description":"Invariant mass of the lepton pair plus jet system, for data, background (pre- and post-reweighting) and three $H\\rightarrow Za$ signal...","name":"Invariant mass of the dilepton+jet system"},{"@id":"https://doi.org/10.17182/hepdata.153859.v2/t5","@type":"Dataset","description":"Regression NN output variable, for data, reweighted background, and three $H\\rightarrow Za$ signal hypotheses ($a\\rightarrow q\\bar{q}/gg$ inclusively). Events are required...","name":"Predicted mass"},{"@id":"https://doi.org/10.17182/hepdata.153859.v2/t6","@type":"Dataset","description":"Classification NN output variable, for data, reweighted background, and three $H\\rightarrow Za$ signal hypotheses ($a\\rightarrow q\\bar{q}/gg$ inclusively). Events are required...","name":"Classification score"},{"@id":"https://doi.org/10.17182/hepdata.153859.v2/t7","@type":"Dataset","description":"Invariant mass of the lepton pair plus jet system for data, reweighted background and its systematic uncertainties (only \"up\" variations...","name":"Pre-fit dilepton+jet mass"},{"@id":"https://doi.org/10.17182/hepdata.153859.v2/t8","@type":"Dataset","description":"Invariant mass of the lepton pair plus jet system for data, reweighted background, and 0.5 GeV signal hypotheses. Events are...","name":"Post-fit dilepton+jet mass"},{"@id":"https://doi.org/10.17182/hepdata.153859.v2/t9","@type":"Dataset","description":"Observed 95$\\%$ CL upper limits on $\\mathcal{B}(H \\to Za)=100\\%$ for $\\mathcal{B}(a \\to gg)=100\\%$, and the expectation under the background-only hypothesis...","name":"Upper limits for $\\mathcal{B}(a \\to gg)=1$"},{"@id":"https://doi.org/10.17182/hepdata.153859.v2/t10","@type":"Dataset","description":"Observed 95$\\%$ confidence level upper limits on $\\mathcal{B}(H \\to Za)=100\\%$ for $\\mathcal{B}(a\\rightarrow q\\bar{q})=100\\%$, and the expectation under the background-only hypothesis...","name":"Upper limits for $\\mathcal{B}(a\\rightarrow q\\bar{q})=1$"}],"identifier":[{"@type":"PropertyValue","propertyID":"HEPDataRecord","value":"https://www.hepdata.net/record/ins2851948?version=2"},{"@type":"PropertyValue","propertyID":"HEPDataRecordAlt","value":"https://www.hepdata.net/record/153859"}],"inLanguage":"en","name":"Search for Higgs boson decays into a $Z$ boson and a light hadronically decaying resonance in 140 fb$^{-1}$ of 13 TeV $p$$p$ collisions with the ATLAS detector","provider":{"@type":"Organization","name":"HEPData"},"publisher":{"@type":"Organization","name":"HEPData"},"url":"https://www.hepdata.net/record/ins2851948?version=2","version":2}