{
  "id": "hep-ph/0412085",
  "version": "v1",
  "published": "2004-12-06T16:35:20.000Z",
  "updated": "2004-12-06T16:35:20.000Z",
  "title": "Evidence for Quark Spin-flip in Pomeron Exchange",
  "authors": [
    "A. Donnachie"
  ],
  "comment": "6 pages, 3 figures",
  "journal": "Phys.Lett. B611 (2005) 255-259",
  "doi": "10.1016/j.physletb.2005.02.036",
  "categories": [
    "hep-ph"
  ],
  "abstract": "Spin-parity analyses of the $\\omega\\pi$ system in the reaction $\\gamma p \\to (\\omega\\pi) p$ for photon laboratory energies from 20 to 70 GeV have shown that production of the $J^P=1^+$ $b_1(1235)$ meson dominates, with a $J^P=1^-$ background at the level of 20%. Using vector-meson dominance arguments, this background is shown to be consistent with the data on $e^+e^- \\to \\omega\\pi$. The energy dependence of the data imply that the mechanism is a combination of Reggeon and Pomeron exchange. Assuming that the latter is relevant only for the $J^P = 1^-$ component and extrapolating to W=200 GeV, it is argued that this accounts for most of the preliminary $\\omega\\pi$ signal observed by the H1 Collaboration in the same reaction. A residual peak can be ascribed to the $b_1(1235)$, which requires a quark spin-flip from Pomeron exchange. Precisely the same mechanism occurs in the reaction $\\pi p \\to a_1(1260) p$.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2004-12-06T16:35:20.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "pomeron exchange",
      "quark spin-flip",
      "photon laboratory energies",
      "vector-meson dominance arguments",
      "h1 collaboration"
    ],
    "tags": [
      "journal article"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 6,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "inspire": 666271
    }
  }
}