{
  "id": "1208.4292",
  "version": "v1",
  "published": "2012-08-21T15:43:28.000Z",
  "updated": "2012-08-21T15:43:28.000Z",
  "title": "Polarization in Quarkonium Production",
  "authors": [
    "James S. Russ",
    "on behalf of the CDF Collaboration"
  ],
  "comment": "6 pages, 10 figures, submission to FPCP2012",
  "categories": [
    "hep-ex"
  ],
  "abstract": "Production mechanisms for quarkonium states in hadronic collisions remain difficult to understand. The decay angular distributions of J/$\\psi$ or $\\Upsilon(nS)$ states into $\\mu^+ \\mu^-$ final states are sensitive to the matrix elements in the production process and provide a unique tool to evaluate different models. This talk will focus on new results for the spin alignment of $\\Upsilon(nS)$ states produced in $p\\bar{p}$ collisions at $\\sqrt{s}$ = 1.96 TeV using the CDF II detector at the Fermilab Tevatron. The data sample corresponds to an integrated luminosity of 6.7 fb$^{-1}$. The angular distributions are analyzed as functions of the transverse momentum of the dimuon final state in both the Collins-Soper and the s-channel helicity frames using a unique data-driven background determination method. Consistency of the analysis is checked by comparing frame-invariant quantities derived from parametrizations of the angular distributions measured in each choice of reference frame. This analysis is the first to quantify the complete three-dimensional angular distribution of $\\Upsilon(1S), \\Upsilon(2S)$ and $\\Upsilon(3S)$ decays. The decays are nearly isotropic in all frames, even when produced with large transverse momentum.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2012-08-21T15:43:28.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "quarkonium production",
      "unique data-driven background determination method",
      "polarization",
      "complete three-dimensional angular distribution",
      "final state"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 6,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "inspire": 1128461,
      "adsabs": "2012arXiv1208.4292R"
    }
  }
}