{
  "id": "0709.0282",
  "version": "v1",
  "published": "2007-09-03T17:43:23.000Z",
  "updated": "2007-09-03T17:43:23.000Z",
  "title": "Theoretical progress on the V_us determination from tau decays",
  "authors": [
    "Elvira Gamiz",
    "Matthias Jamin",
    "Antonio Pich",
    "Joaquim Prades",
    "Felix Schwab"
  ],
  "comment": "Invited talk at the Kaon International Conference -KAON'07- (Frascati, Italy, May 21-25, 2007)",
  "journal": "PoSKAON:008,2008",
  "categories": [
    "hep-ph",
    "hep-ex"
  ],
  "abstract": "A very precise determination of V_us can be obtained from the semi-inclusive hadronic decay width of the tau lepton into final states with strangeness. The ratio of the Cabibbo-suppressed and Cabibbo-allowed tau decay widths directly measures (V_us/V_ud)^2, up to very small SU(3)-breaking corrections which can be theoretically estimated with the needed accuracy. Together with previous LEP and CLEO data, the recent measurements by Babar and Belle of some Cabibbo-suppressed tau decays imply V_us= 0.2165 +- 0.0026_exp +- 0.0005_th, which is already competitive with the standard extraction from K_l3 decays. The uncertainty is largely dominated by experimental errors and should be easily reduced with the high statistics of the B factories, providing the most accurate determination of this parameter. A 1% experimental precision on the Cabibbo-suppressed tau decay width would translate into a 0.6% uncertainty on V_us.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2007-09-03T17:43:23.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "theoretical progress",
      "determination",
      "tau decay widths directly measures",
      "cabibbo-allowed tau decay widths",
      "semi-inclusive hadronic decay width"
    ],
    "tags": [
      "conference paper",
      "journal article"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 0,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "inspire": 759686,
      "adsabs": "2007arXiv0709.0282G"
    }
  }
}