{
  "id": "0705.4029",
  "version": "v2",
  "published": "2007-05-28T11:31:44.000Z",
  "updated": "2007-09-23T00:24:15.000Z",
  "title": "Branching Ratios and CP Asymmetries of B \\to a_1(1260) πand a_1(1260) K Decays",
  "authors": [
    "Kwei-Chou Yang"
  ],
  "comment": "20 pages, 1 figure, 4 tables, typos corrected, some discussions added, version to appear in PRD",
  "journal": "Phys.Rev.D76:094002,2007",
  "doi": "10.1103/PhysRevD.76.094002",
  "categories": [
    "hep-ph",
    "hep-ex"
  ],
  "abstract": "We present the studies of the decays $B\\to a_1(1260) \\pi$ and $a_1(1260) K$ within the framework of QCD factorization. Due to the G-parity, unlike the vector meson, the chiral-odd two-parton light-cone distribution amplitudes of the $a_1$ are antisymmetric under the exchange of quark and anti-quark momentum fractions in the SU(2) limit. The branching ratios for $a_1 \\pi$ modes are sensitive to tree--penguin interference. The resultant ${\\cal B}(B^0 \\to a_1^\\pm \\pi^\\mp)$ are in good agreement with the data. However, using the current Cabibbo--Kobayashi--Maskawa angles, $\\beta=22.0^\\circ$ and $\\gamma=59.0^\\circ$, our results for the mixing-induced parameter $S$ and $\\alpha_{\\rm eff}$ differ from the measurements of the time-dependent CP asymmetries in the decay $B^0\\to a_1^\\pm \\pi^\\mp$ at about the $3.7\\sigma$ level. This puzzle may be resolved by using a larger $\\gamma \\gtrsim 80^\\circ$. For $a_1 K$ modes, the annihilation topologies give sizable contributions and are sensitive to the first Gegenbauer moment of the leading-twist tensor (chiral-odd) distribution amplitude of the $a_1$ meson. The $B\\to a_1 K$ amplitudes resemble the corresponding $B\\to \\pi K$ ones very much. Taking the ratios of corresponding CP-averaged $a_1 K$ and $\\pi K$ branching ratios, we can extract information relevant to the electroweak penguins and annihilations. The existence of new-physics in the electroweak penguin sector and final state interactions during decays can thus be explored.",
  "revisions": [
    {
      "version": "v2",
      "updated": "2007-09-23T00:24:15.000Z"
    }
  ],
  "analyses": {
    "subjects": [
      "14.40.Cs",
      "12.38.Bx",
      "13.25.Hw"
    ],
    "keywords": [
      "branching ratios",
      "cp asymmetries",
      "chiral-odd two-parton light-cone distribution amplitudes",
      "extract information relevant",
      "anti-quark momentum fractions"
    ],
    "tags": [
      "journal article"
    ],
    "publication": {
      "publisher": "APS",
      "journal": "Physical Review D",
      "year": 2007,
      "month": "Nov",
      "volume": 76,
      "number": 9,
      "pages": "094002"
    },
    "note": {
      "typesetting": "TeX",
      "pages": 20,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "inspire": 751598,
      "adsabs": "2007PhRvD..76i4002Y"
    }
  }
}