{
  "id": "2105.13330",
  "version": "v1",
  "published": "2021-05-27T17:38:40.000Z",
  "updated": "2021-05-27T17:38:40.000Z",
  "title": "Prospects for $B_{c}^+\\to τ^+ ν_τ$ at FCC-ee",
  "authors": [
    "Yasmine Amhis",
    "Clément Helsens",
    "Donal Hill",
    "Olcyr Sumensari"
  ],
  "comment": "31 pages, 10 figures",
  "categories": [
    "hep-ex",
    "hep-ph"
  ],
  "abstract": "This paper presents the prospects for a precise measurement of the branching fraction of the leptonic $B_{c}^+\\to \\tau^+ \\nu_\\tau$ decay at the Future Circular Collider (FCC-ee) running at the $Z$-pole. A detailed description of the simulation and analysis framework is provided. To select signal candidates, two Boosted Decision Tree algorithms are employed and optimised. The first stage suppresses inclusive $b\\bar{b}$, $c\\bar{c}$, and $q\\bar{q}$ backgrounds using event-based topological information. A second stage utilises the properties of the hadronic $\\tau^{+} \\to \\pi^+ \\pi^+ \\pi^- \\bar{\\nu}_\\tau$ decay to further suppress these backgrounds, and is also found to achieve high rejection for the $B^+\\to \\tau^+ \\nu_\\tau$ background. The number of $B_{c}^+\\to \\tau^+ \\nu_\\tau$ candidates is estimated for various Tera-$Z$ scenarios, and the potential precision of signal yield and branching fraction measurements evaluated. The phenomenological impact of such measurements on various New Physics scenarios is also explored.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2021-05-27T17:38:40.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "background",
      "achieve high rejection",
      "select signal candidates",
      "boosted decision tree algorithms",
      "first stage suppresses"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 31,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}