{"@context":"http://schema.org","@id":"https://doi.org/10.17182/hepdata.167264.v1","@reverse":{"isBasedOn":[{"@type":"ScholarlyArticle","identifier":{"@type":"PropertyValue","propertyID":"URL","value":"https://inspirehep.net/literature/3087833"}}]},"@type":"Dataset","additionalType":"Collection","author":{"@type":"Organization","name":"ATLAS Collaboration"},"creator":{"@type":"Organization","name":"ATLAS Collaboration"},"datePublished":"2026","description":"ATLAS-CERN-LHC.  The top-quark mass is measured using top-quark decays producing an isolated lepton and $J/\\psi$ meson reconstructed in its $\\mu^+\\mu^-$ decay mode. The data sample was recorded with the ATLAS detector in proton--proton collisions at a centre-of-mass energy of $\\sqrt{s}=13$ TeV during Run 2 of the Large Hadron Collider, corresponding to an integrated luminosity of 140 fb$^{-1}$. The measurement is based on the invariant mass $m(\\ell \\mu^+\\mu^-)$ of the system made of the isolated lepton $\\ell$ from the $W$ boson decay and the non-isolated $\\mu^+\\mu^-$ pair from a $J/\\psi$ decay of a $b$-hadron, exploiting its sensitivity to the top-quark mass. An unbinned maximum-likelihood fit to the $m(\\ell \\mu^+\\mu^-)$ distribution is performed to extract the top-quark mass. The top-quark mass is measured to be $m_{top} = 172.17 \\pm 0.80 (stat) \\pm 0.81 (syst) \\pm 1.07 (recoil)$ GeV, with a total uncertainty of 1.56 GeV. The third uncertainty arises from changing the dipole parton shower gluon-recoil scheme used in top-quark decays.","hasPart":[{"@id":"https://doi.org/10.17182/hepdata.167264.v1/t1","@type":"Dataset","description":"Top mass measurement result.","name":"Result"},{"@id":"https://doi.org/10.17182/hepdata.167264.v1/t2","@type":"Dataset","description":"Number of selected events in data after the final selection. Also shown are the expected numbers of $t\\bar{t}$ and single-top-quark...","name":"Table 2"},{"@id":"https://doi.org/10.17182/hepdata.167264.v1/t3","@type":"Dataset","description":"Impact of sources of uncertainty in $m_{top}$. Each row of the table corresponds to a group of individual systematic variations....","name":"Table 3"},{"@id":"https://doi.org/10.17182/hepdata.167264.v1/t4","@type":"Dataset","description":"List of all the individual sources of systematic uncertainty considered in the analysis. The individual sources, each corresponding to an...","name":"All Systematic Uncertainties"}],"identifier":[{"@type":"PropertyValue","propertyID":"HEPDataRecord","value":"https://www.hepdata.net/record/ins3087833?version=1"},{"@type":"PropertyValue","propertyID":"HEPDataRecordAlt","value":"https://www.hepdata.net/record/167264"}],"inLanguage":"en","name":"Measurement of the top-quark mass using decays with a $J/\u03c8$ meson at $\\sqrt{s}=$13 TeV with the ATLAS detector","provider":{"@type":"Organization","name":"HEPData"},"publisher":{"@type":"Organization","name":"HEPData"},"url":"https://www.hepdata.net/record/ins3087833?version=1","version":1}