{
  "id": "hep-ex/0406028",
  "version": "v1",
  "published": "2004-06-10T11:36:06.000Z",
  "updated": "2004-06-10T11:36:06.000Z",
  "title": "Direct Measurements of the Branching Fractions for $D^0 \\to K^-e^+ν_e$ and $D^0 \\to π^-e^+ν_e$ and Determinations of the Form Factors $f_{+}^{K}(0)$ and $f^π_{+}(0)$",
  "authors": [
    "BES Collaboration"
  ],
  "comment": "6 pages, 5 figures",
  "journal": "Phys.Lett.B597:39-46,2004",
  "doi": "10.1016/j.physletb.2004.07.004",
  "categories": [
    "hep-ex"
  ],
  "abstract": "The absolute branching fractions for the decays $D^0 \\to K^-e ^+\\nu_e$ and $D^0 \\to \\pi^-e^+\\nu_e$ are determined using $7584\\pm 198 \\pm 341$ singly tagged $\\bar D^0$ sample from the data collected around 3.773 GeV with the BES-II detector at the BEPC. In the system recoiling against the singly tagged $\\bar D^0$ meson, $104.0\\pm 10.9$ events for $D^0 \\to K^-e ^+\\nu_e$ and $9.0 \\pm 3.6$ events for $D^0 \\to \\pi^-e^+\\nu_e$ decays are observed. Those yield the absolute branching fractions to be $BF(D^0 \\to K^-e^+\\nu_e)=(3.82 \\pm 0.40\\pm 0.27)%$ and $BF(D^0 \\to \\pi^-e^+\\nu_e)=(0.33 \\pm 0.13\\pm 0.03)%$. The vector form factors are determined to be $|f^K_+(0)| = 0.78 \\pm 0.04 \\pm 0.03$ and $|f^{\\pi}_+(0)| = 0.73 \\pm 0.14 \\pm 0.06$. The ratio of the two form factors is measured to be $|f^{\\pi}_+(0)/f^K_+(0)|= 0.93 \\pm 0.19 \\pm 0.07$.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2004-06-10T11:36:06.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "direct measurements",
      "absolute branching fractions",
      "determinations",
      "vector form factors",
      "bes-ii detector"
    ],
    "tags": [
      "journal article"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 6,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "inspire": 652163
    }
  }
}