{
  "id": "1803.05949",
  "version": "v1",
  "published": "2018-03-15T18:58:29.000Z",
  "updated": "2018-03-15T18:58:29.000Z",
  "title": "Asymmetric regularization of the ground and excited state of the helium-4 nucleus",
  "authors": [
    "Johannes Kirscher",
    "Harald W. Grießhammer"
  ],
  "comment": "13 pages, 7 figures, 1 table",
  "categories": [
    "nucl-th",
    "physics.atom-ph"
  ],
  "abstract": "We find the threshold structure of the two- and three-nucleon systems, with the deuteron and 3H/3He as the only bound nuclei, sufficient to predict a pair of four-nucleon states: a deeply bound state which is identified with the helium-4 ground state, and a shallow, unstable state at an energy 0.38(25) MeV above the triton-proton threshold which is consistent with data on the first excited state of helium-4. The analysis employs the framework of Pionless EFT at leading order with a generalized regulator prescription which probes renormalization-group invariance of the two states with respect to higher-order perturbations including asymmetrical disturbances of the short-distance structure of the interaction. In addition to this invariance of the bound-state spectrum and the diagonal triton-proton 1S0 phase shifts in the helium-4 channel with respect to the short-distance structure of the nuclear interaction, our multi-channel calculations with a resonating-group method demonstrate the increasing sensitivity of nuclei to the neutron-proton P-wave interaction. We show that two-nucleon phase shifts, the triton channel, and three-nucleon negative-parity channels are less sensitive with respect to enhanced two-nucleon P-wave attraction than the four-nucleon triton-proton 1S0 phase shifts.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2018-03-15T18:58:29.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "excited state",
      "asymmetric regularization",
      "four-nucleon triton-proton 1s0 phase shifts",
      "diagonal triton-proton 1s0 phase shifts",
      "short-distance structure"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 13,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}