{
  "id": "hep-ph/0202194",
  "version": "v2",
  "published": "2002-02-20T15:52:48.000Z",
  "updated": "2002-02-27T11:58:37.000Z",
  "title": "On the Infrared Exponent for Gluon and Ghost Propagation in Landau Gauge QCD",
  "authors": [
    "Christoph Lerche",
    "Lorenz von Smekal"
  ],
  "comment": "22 Pages, 10 Figures, LaTeX2e, revtex4, some notes and references added in response to communications",
  "journal": "Phys.Rev. D65 (2002) 125006",
  "doi": "10.1103/PhysRevD.65.125006",
  "categories": [
    "hep-ph",
    "hep-th"
  ],
  "abstract": "In the covariant description of confinement, one expects the ghost correlations to be infrared enhanced. Assuming ghost dominance, the long-range behavior of gluon and ghost correlations in Landau gauge QCD is determined by one exponent kappa. The gluon propagator is infrared finite (vanishing) for kappa =1/2 (kappa > 1/2) which is still under debate. Here, we study critical exponent and coupling for the infrared conformal behavior from the asymptotic form of the solutions to the Dyson-Schwinger equations in an ultraviolet finite expansion scheme. The value for kappa is directly related to the ghost-gluon vertex. Assuming that it is regular in the infrared, one obtains kappa = 0.595. This value maximizes the critical coupling alpha_c(kappa), yielding alpha_c^max = (4 Pi/Nc) 0.709 approx. 2.97 for Nc=3. For larger kappa the vertex acquires an infrared singularity in the gluon momentum, smaller ones imply infrared singular ghost legs. Variations in alpha_c remain within 5% from kappa = 0.5 to 0.7. Above this range, alpha_c decreases more rapidly with alpha_c -> 0 as kappa -> 1 which sets the upper bound on kappa.",
  "revisions": [
    {
      "version": "v2",
      "updated": "2002-02-27T11:58:37.000Z"
    }
  ],
  "analyses": {
    "subjects": [
      "12.38.Aw",
      "11.10.Jj",
      "11.10.Gh",
      "12.38.Lg"
    ],
    "keywords": [
      "landau gauge qcd",
      "ghost propagation",
      "infrared exponent",
      "ghost correlations",
      "ultraviolet finite expansion scheme"
    ],
    "tags": [
      "journal article",
      "famous paper"
    ],
    "publication": {
      "publisher": "APS",
      "journal": "Phys. Rev. D"
    },
    "note": {
      "typesetting": "RevTeX",
      "pages": 22,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "inspire": 583180
    }
  }
}