{
  "id": "nucl-th/9712051",
  "version": "v1",
  "published": "1997-12-15T08:22:33.000Z",
  "updated": "1997-12-15T08:22:33.000Z",
  "title": "$ππ$ scattering in the $ρ$-meson channel at finite temperature",
  "authors": [
    "Y. B. He",
    "J. Hüfner",
    "S. P. Klevansky",
    "P. Rehberg"
  ],
  "comment": "25 pages, 12 figures, to appear in Nucl. Phys. A",
  "journal": "Nucl.Phys. A630 (1998) 719-742",
  "doi": "10.1016/S0375-9474(98)00807-0",
  "categories": [
    "nucl-th",
    "hep-ph"
  ],
  "abstract": "We study $\\pi\\pi$ scattering in the I=1, $J^P=1^-$ channel at finite temperature in the framework of the extended Nambu-Jona-Lasinio model that explicitly includes vector and axial-vector degrees of freedom in addition to the usual scalar and pseudoscalar sector. The S-matrix in the coupled channels $q\\bar q$ and $\\pi \\pi$ is constructed via $\\rho$-exchange in the $s$-channel. The self-energy of the $\\rho$-meson contains both quark and pion loop contributions. The analytic structure of the S-matrix for $T\\geq 0$ is investigated and the motion of the $\\rho$-pole as a function of coupling constant and temperature is followed in the complex $\\sqrt{s}$-plane. For numerical calculations, parameters are chosen in order that $m_\\pi$, $f_\\pi$ and the experimental $\\pi\\pi$ phase shifts $\\delta_1^1$ at zero temperature are reproduced, and then the behavior of the $\\rho$-pole as well as the $\\pi\\pi$ cross section is investigated as a function of the temperature. We find that the position of the $\\rho$ mass stays practically constant for $0\\leq T\\leq 130$ MeV, and then moves down in energy by about 200 MeV for 130 MeV$\\leq T\\leq 230$ MeV.",
  "revisions": [
    {
      "version": "v1",
      "updated": "1997-12-15T08:22:33.000Z"
    }
  ],
  "analyses": {
    "subjects": [
      "12.39.Ba",
      "21.65.+f",
      "24.85.+p"
    ],
    "keywords": [
      "finite temperature",
      "meson channel",
      "scattering",
      "mass stays practically constant",
      "pion loop contributions"
    ],
    "tags": [
      "journal article"
    ],
    "publication": {
      "publisher": "Elsevier",
      "journal": "Nucl. Phys. A"
    },
    "note": {
      "typesetting": "TeX",
      "pages": 25,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "inspire": 452407
    }
  }
}