{
  "id": "1405.3601",
  "version": "v2",
  "published": "2014-05-14T17:59:59.000Z",
  "updated": "2014-12-18T18:15:44.000Z",
  "title": "Lifetimes and HQE",
  "authors": [
    "Alexander Lenz"
  ],
  "comment": "53 pages, invited contribution to the Kolya Uraltsev Memorial Book; comments are welcome; typos corrected; nicer style file and new experimental results included",
  "categories": [
    "hep-ph",
    "hep-ex"
  ],
  "abstract": "Kolya Uraltsev was one of the inventors of the Heavy Quark Expansion (HQE), that describes inclusive weak decays of hadrons containing heavy quarks and in particular lifetimes. Besides giving a pedagogic introduction to the subject, we review the development and the current status of the HQE, which just recently passed several non-trivial experimental tests with an unprecedented precision. In view of many new experimental results for lifetimes of heavy hadrons, we also update several theory predictions: $\\tau (B^+) / \\tau (B_d) = 1.04^{+0.05}_{-0.01} \\pm 0.02 \\pm 0.01$, $\\tau (B_s) / \\tau (B_d) = 1.001 \\pm 0.002$, $\\tau (\\Lambda_b)/ \\tau (B_d) = 0.935 \\pm 0.054$ and $\\bar {\\tau} (\\Xi_b^0) / \\bar{\\tau} (\\Xi_b^+) = 0.95 \\pm 0.06$. The theoretical precision is currently strongly limited by the unknown size of the non-perturbative matrix elements of four-quark operators, which could be determined with lattice simulations.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2014-05-14T17:59:59.000Z",
      "comment": "53 pages, invited contribution to the Kolya Uraltsev Memorial Book; comments are welcome",
      "journal": null,
      "doi": null
    },
    {
      "version": "v2",
      "updated": "2014-12-18T18:15:44.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "heavy quark expansion",
      "hadrons containing heavy quarks",
      "non-trivial experimental tests",
      "inclusive weak decays",
      "lattice simulations"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 53,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "inspire": 1296083,
      "adsabs": "2014arXiv1405.3601L"
    }
  }
}