{
  "id": "1705.01633",
  "version": "v1",
  "published": "2017-05-03T21:27:39.000Z",
  "updated": "2017-05-03T21:27:39.000Z",
  "title": "Validity of the Weizsäcker-Williams Approximation and the Analysis of Beam Dump Experiments: Production of an axion, a dark photon, or a new axial-vector boson",
  "authors": [
    "Yu-Sheng Liu",
    "Gerald A. Miller"
  ],
  "comment": "21 pages, 9 figures. arXiv admin note: substantial text overlap with arXiv:1609.06781",
  "categories": [
    "hep-ph",
    "hep-ex",
    "nucl-ex",
    "nucl-th"
  ],
  "abstract": "Beam dump experiments have been used to search for new particles, $\\phi$, with null results interpreted in terms of limits on masses $m_\\phi$ and coupling constants $\\epsilon$. However these limits have been obtained by using approximations [including the Weizs\\\"{a}cker-Williams (WW) approximation] or Monte-Carlo simulations. We display methods to obtain the cross section and the resulting particle production rates without using approximations on the phase space integral or Monte-Carlo simulations. In our previous work we examined the case of the new scalar boson production; in this paper we explore all possible new spin-0 and spin-1 particles. We show that the approximations cannot be used to obtain accurate values of cross sections. The corresponding exclusion plots differ by substantial amounts when seen on a linear scale. Furthermore, a new region ($m_\\phi<2m_e$) of parameter space can be explored without using one of the common approximations, $m_\\phi\\gg m_e$. We derive new expressions for the three photon decays of dark photon and four photon decays of new axial-vector bosons. As a result, the production cross section and exclusion region of different low mass ($m_\\phi<2m_e$) bosons are very different. Moreover, our method can be used as a consistency check for Monte-Carlo simulations.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2017-05-03T21:27:39.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "beam dump experiments",
      "axial-vector boson",
      "dark photon",
      "weizsäcker-williams approximation",
      "monte-carlo simulations"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 21,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}