{
  "id": "1709.06840",
  "version": "v1",
  "published": "2017-09-20T12:52:52.000Z",
  "updated": "2017-09-20T12:52:52.000Z",
  "title": "Electromagnetic Strength Distributions from the Ab Initio No-Core Shell Model",
  "authors": [
    "Christina Stumpf",
    "Tobias Wolfgruber",
    "Robert Roth"
  ],
  "comment": "6 pages, 3 figures",
  "categories": [
    "nucl-th",
    "nucl-ex"
  ],
  "abstract": "We present an ab initio approach for the description of collective excitations and transition strength distributions of arbitrary nuclei up into the sd-shell that based on the No-Core Shell Model in combination with the Lanczos strength-function method. Starting from two- and three-nucleon interactions from chiral effective field theory, we investigate the electric monopole, dipole, and quadrupole response of the even oxygen isotopes from 16-O to 24-O. The method describes the full energy range from low-lying excitations to the giant resonance region and beyond in a unified and consistent framework, including a complete description of fragmentation and fine-structure. This opens unique opportunities for understanding dynamic properties of nuclei from first principles and to further constrain nuclear interactions. We demonstrate the computational efficiency and the robust model-space convergence of our approach and compare to established approximate methods, such as the Random Phase Approximation, shedding new light on their deficiencies.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2017-09-20T12:52:52.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "ab initio no-core shell model",
      "electromagnetic strength distributions",
      "full energy range",
      "lanczos strength-function method",
      "transition strength distributions"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 6,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}