{
  "id": "0806.4040",
  "version": "v2",
  "published": "2008-06-25T07:57:57.000Z",
  "updated": "2009-06-11T16:33:32.000Z",
  "title": "New Constraints on Radiative Decay of Long-Lived Particles in Big Bang Nucleosynthesis with New $^4$He Photodisintegration Data",
  "authors": [
    "Motohiko Kusakabe",
    "Toshitaka Kajino",
    "Takashi Yoshida",
    "Tatsushi Shima",
    "Yasuki Nagai",
    "Toshiteru Kii"
  ],
  "comment": "10 pages, 7 figures, conclusion not changed, to be published in PRD",
  "journal": "Phys.Rev.D79:123513,2009",
  "doi": "10.1103/PhysRevD.79.123513",
  "categories": [
    "astro-ph",
    "hep-ph"
  ],
  "abstract": "A recent measurement of $^4$He photodisintegration reactions, $^4$He($\\gamma$,$p$)$^3$H and $^4$He($\\gamma$,$n$)$^3$He with laser-Compton photons shows smaller cross sections than those estimated by other previous experiments at $E_\\gamma \\lesssim 30$ MeV. We study big-bang nucleosynthesis with the radiative particle decay using the new photodisintegration cross sections of $^4$He as well as previous data. The sensitivity of the yields of all light elements D, T, $^3$He, $^4$He, $^6$Li, $^7$Li and $^7$Be to the cross sections is investigated. The change of the cross sections has an influence on the non-thermal yields of D, $^3$He and $^4$He. On the other hand, the non-thermal $^6$Li production is not sensitive to the change of the cross sections at this low energy, since the non-thermal secondary synthesis of $^6$Li needs energetic photons of $E_\\gamma \\gtrsim 50$ MeV. The non-thermal nucleosynthesis triggered by the radiative particle decay is one of candidates of the production mechanism of $^6$Li observed in metal-poor halo stars (MPHSs). In the parameter region of the radiative particle lifetime and the emitted photon energy which satisfies the $^6$Li production above the abundance level observed in MPHSs, the change of the photodisintegration cross sections at $E_\\gamma \\lesssim 30$ MeV as measured in the recent experiment leads to $\\sim 10$% reduction of resulting $^3$He abundance, whereas the $^6$Li abundance does not change for this change of the cross sections of $^4$He($\\gamma$,$p$)$^3$H and $^4$He($\\gamma$,$n$)$^3$He. The $^6$Li abundance, however, could show a sizable change and therefore the future precise measurement of the cross sections at high energy $E_\\gamma \\gtrsim$ 50 MeV is highly required.",
  "revisions": [
    {
      "version": "v2",
      "updated": "2009-06-11T16:33:32.000Z"
    }
  ],
  "analyses": {
    "subjects": [
      "25.10.+s",
      "98.80.Cq",
      "26.35.+c",
      "98.80.Es"
    ],
    "keywords": [
      "big bang nucleosynthesis",
      "photodisintegration data",
      "radiative decay",
      "long-lived particles",
      "photodisintegration cross sections"
    ],
    "tags": [
      "journal article"
    ],
    "publication": {
      "publisher": "APS",
      "journal": "Physical Review D",
      "year": 2009,
      "month": "Jun",
      "volume": 79,
      "number": 12,
      "pages": 123513
    },
    "note": {
      "typesetting": "TeX",
      "pages": 10,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "inspire": 789078,
      "adsabs": "2009PhRvD..79l3513K"
    }
  }
}