{
  "id": "2207.07421",
  "version": "v1",
  "published": "2022-07-15T12:00:25.000Z",
  "updated": "2022-07-15T12:00:25.000Z",
  "title": "Extensive study of nuclear uncertainties and their impact on the r-process nucleosynthesis in neutron star mergers",
  "authors": [
    "I. Kullmann",
    "S. Goriely",
    "O. Just",
    "A. Bauswein",
    "H. -T. Janka"
  ],
  "comment": "26 pages, 22 figures, submitted to MNRAS",
  "categories": [
    "astro-ph.HE",
    "nucl-th"
  ],
  "abstract": "Theoretically predicted yields of elements created by the rapid neutron capture (r-) process carry potentially large uncertainties associated with incomplete knowledge of nuclear properties as well as approximative hydrodynamical modelling of the matter ejection processes. We present an in-depth study of the nuclear uncertainties by systematically varying theoretical nuclear input models that describe the experimentally unknown neutron-rich nuclei. This includes two frameworks for calculating the radiative neutron capture rates and six, four and four models for the nuclear masses, $\\beta$-decay rates and fission properties, respectively. Our r-process nuclear network calculations are based on detailed hydrodynamical simulations of dynamically ejected material from NS-NS or NS-BH binary mergers plus the secular ejecta from BH-torus systems. The impact of nuclear uncertainties on the r-process abundance distribution and early radioactive heating rate is found to be modest (within a factor $\\sim 20$ for individual $A>90$ nuclei and a factor 2 for the heating rate), however the impact on the late-time heating rate is more significant and depends strongly on the contribution from fission. We witness significantly larger sensitivity to the nuclear physics input if only a single trajectory is used compared to considering ensembles of $\\sim$200-300 trajectories, and the quantitative effects of the nuclear uncertainties strongly depend on the adopted conditions for the individual trajectory. We use the predicted Th/U ratio to estimate the cosmochronometric age of six metal-poor stars to set a lower limit of the age of the Galaxy and find the impact of the nuclear uncertainties to be up to 2 Gyr.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2022-07-15T12:00:25.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "nuclear uncertainties",
      "neutron star mergers",
      "r-process nucleosynthesis",
      "theoretical nuclear input models",
      "carry potentially large uncertainties"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 26,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}