{
  "id": "1101.6053",
  "version": "v3",
  "published": "2011-01-31T19:28:20.000Z",
  "updated": "2016-10-20T22:30:55.000Z",
  "title": "On $D\\to X_u l^+ l^-$ within the Standard Model and Frameworks like the Littlest Higgs Model with T Parity",
  "authors": [
    "Ayan Paul",
    "Ikaros I. Bigi",
    "Stefan Recksiegel"
  ],
  "comment": "24 Pages, 12 figures. V2 contains corrections to the Appendix A. V3 fixes an error in eq. 10",
  "journal": "Phys.Rev.D83: 114006, 2011",
  "doi": "10.1103/PhysRevD.83.114006",
  "categories": [
    "hep-ph",
    "hep-ex"
  ],
  "abstract": "The $D\\to X_u l^+ l^-$ transitions -- branching ratios, forward-backward asymmetry $A^c_{FB}$, the CP asymmetry $A^c_{CP}$ and the CP asymmetry in the forward-backward asymmetry $A^{CP}_{FB}$ -- have two sources: for $D^{\\pm}$ they represent a pure $\\Delta C=1$ & $\\Delta Q=0$ current interaction whereas neutral $D$ mesons can also communicate via their anti-hadron. Standard Model (SM) contributions to BR$(D\\to X_u l^+ l^-)$ come primarily from long distance dynamics, which overshadow short distance contributions by several orders of magnitude; still they fall much below the present upper experimental bounds. Even the SM contributions to $A^c_{FB}$, $A^c_{CP}$ and $A^{CP}_{FB}$ are tiny, quite unlike in beauty hadrons. The branching ratios are hardly dented by contributions from the Littlest Higgs Models with T parity (LHT) even in the short distance regime, let alone in the SM long distances dynamics. Yet the asymmetries $A^c_{FB}$, $A^c_{CP}$ and $A^{CP}_{FB}$ in these New Physics models can be enhanced over SM predictions, as they arise purely from short distance dynamics; this can occur in particular for $A^c_{FB}$ and $A^{CP}_{FB}$ which get enhanced by orders of magnitudes. Even such enhancements hardly reach absolute sizes for observable experimental effects for $A^c_{FB}$ and $A^c_{CP}$. However LHT contributions to $A^{CP}_{FB}$ could be measured in experiments like the LHCb and the SuperB Collaboration. These results lead us to draw further conclusions on FCNCs within LHT-like models through some simple scaling arguments that encapsulate the essence of flavour dynamics in and beyond the Standard Model.",
  "revisions": [
    {
      "version": "v2",
      "updated": "2011-06-01T16:57:52.000Z",
      "title": "On D\\to X_u l^+ l^- within the Standard Model and Frameworks like the Littlest Higgs Model with T Parity",
      "abstract": "The D\\to X_u l^+ l^- transitions -- branching ratios, forward-backward asymmetry A^c_{FB}, the CP asymmetry A^c_{CP} and the CP asymmetry in the forward-backward asymmetry A^{CP}_{FB} -- have two sources: for D^{\\pm} they represent a pure \\Delta C=1 & \\Delta Q=0 current interaction whereas neutral D mesons can also communicate via their anti-hadron. Standard Model (SM) contributions to BR(D\\to X_u l^+ l^-) come primarily from long distance dynamics, which overshadow short distance contributions by several orders of magnitude; still they fall much below the present upper experimental bounds. Even the SM contributions to A^c_{FB}, A^c_{CP} and A^{CP}_{FB} are tiny, quite unlike in beauty hadrons. The branching ratios are hardly dented by contributions from the Littlest Higgs Models with T parity (LHT) even in the short distance regime, let alone in the SM long distances dynamics. Yet the asymmetries A^c_{FB}, A^c_{CP} and A^{CP}_{FB} in these New Physics models can be enhanced over SM predictions, as they arise purely from short distance dynamics; this can occur in particular for A^c_{FB} and A^{CP}_{FB} which get enhanced by orders of magnitudes. Even such enhancements hardly reach absolute sizes for observable experimental effects for A^c_{FB} and A^c_{CP}. However LHT contributions to A^{CP}_{FB} could be measured in experiments like the LHCb and the SuperB Collaboration. These results lead us to draw further conclusions on FCNCs within LHT-like models through some simple scaling arguments that encapsulate the essence of flavour dynamics in and beyond the Standard Model.",
      "comment": "24 Pages, 12 figures. V2 contains corrections to the Appendix A",
      "journal": "Phys.Rev.D83:114006,2011"
    },
    {
      "version": "v3",
      "updated": "2016-10-20T22:30:55.000Z"
    }
  ],
  "analyses": {
    "subjects": [
      "11.15.Ex",
      "13.20.Fc",
      "12.15.Ff"
    ],
    "keywords": [
      "littlest higgs model",
      "standard model",
      "cp asymmetry",
      "distance dynamics",
      "long distance"
    ],
    "tags": [
      "journal article"
    ],
    "publication": {
      "publisher": "APS",
      "journal": "Phys. Rev. D",
      "year": 2011,
      "month": "Jun",
      "volume": 83,
      "number": 11,
      "pages": 114006
    },
    "note": {
      "typesetting": "TeX",
      "pages": 24,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "inspire": 886410,
      "adsabs": "2011PhRvD..83k4006P"
    }
  }
}