{
  "id": "1412.6428",
  "version": "v1",
  "published": "2014-12-19T16:39:24.000Z",
  "updated": "2014-12-19T16:39:24.000Z",
  "title": "Observation and measurements of the production of prompt and non-prompt $J/ψ$ mesons in association with a $Z$ boson in $pp$ collisions at $\\sqrt{s}= 8$ TeV with the ATLAS detector",
  "authors": [
    "ATLAS Collaboration"
  ],
  "comment": "14 pages + author list + cover page (29 pages total), 6 figures, 4 tables, submitted to EPJC, All figures including auxiliary figures are available at https://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/BPHY-2014-01/",
  "categories": [
    "hep-ex"
  ],
  "abstract": "The production of a $Z$ boson in association with a $J/\\psi$ meson in proton--proton collisions probes the production mechanisms of quarkonium and heavy flavour in association with vector bosons, and allows studies of multiple parton scattering. Using $20.3$ fb$^{-1}$ of data collected with the ATLAS experiment at the LHC, in $pp$ collisions at $\\sqrt{s}=8$ TeV, the first measurement of associated $Z + J/\\psi$ production is presented for both prompt and non-prompt $J/\\psi$ production, with both signatures having a significance in excess of $5\\sigma$. The inclusive production cross-sections for $Z$ boson production (in $\\mu^+\\mu^-$ or $e^+e^-$ decay modes) in association with prompt and non-prompt $J/\\psi(\\to\\mu^+\\mu^-)$ are measured relative to the inclusive production rate of $Z$ bosons in the same fiducial volume to be $(88\\pm 16\\pm 6) \\times 10^{-8}$ and $(157\\pm 22\\pm 10) \\times 10^{-8}$ respectively. Normalised differential production cross-sections are also determined as a function of the $J/\\psi$ transverse momentum. The fraction of signal events arising from single and double parton scattering is estimated, and a lower limit of $5.3\\ (3.7)$ mb at $68\\ (95)$% confidence level is placed on the effective cross-section regulating double parton interactions.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2014-12-19T16:39:24.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "atlas detector",
      "association",
      "collisions",
      "regulating double parton interactions",
      "cross-section regulating double parton"
    ],
    "publication": {
      "doi": "10.1140/epjc/s10052-015-3406-9"
    },
    "note": {
      "typesetting": "TeX",
      "pages": 14,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "inspire": 1335136,
      "adsabs": "2014arXiv1412.6428A"
    }
  }
}