{
  "id": "1901.01410",
  "version": "v1",
  "published": "2019-01-05T13:08:05.000Z",
  "updated": "2019-01-05T13:08:05.000Z",
  "title": "Making the Heaviest Elements in the Universe: A Review of the Rapid Neutron Capture Process",
  "authors": [
    "John J. Cowan",
    "Christopher Sneden",
    "James E. Lawler",
    "Ani Aprahamian",
    "Michael Wiescher",
    "Karlheinz Langanke",
    "Gabriel Martínez-Pinedo",
    "Friedrich-Karl Thielemann"
  ],
  "comment": "85 pages, 45 figures, 2 tables, submitted to Reviews of Modern Physics",
  "categories": [
    "astro-ph.HE",
    "nucl-ex",
    "nucl-th"
  ],
  "abstract": "The production of about half the heavy elements beyond Fe and Ni is assigned the rapid neutron capture process (r process). The full understanding faces two open questions. (a) The nucleosynthesis path runs close to the neutron-drip line, where presently only limited experimental information is available, and one has to rely on theoretical predictions. (b) While for many years the occurrence of the r process has been associated with supernovae recent studies have cast substantial doubts on this environment. Possibly only a weak r process, not producing the third r-process peak, can be accounted for, while much more neutron-rich conditions are likely responsible for the majority of the heavy r-process elements. Possible scenarios are the mergers of neutron stars (recently observed, GW170817) but include also rare classes of supernovae/hypernovae with polar jet ejecta (and possibly also accretion disk outflows in case of black hole formation) related to the collapse of fast rotating massive stars with high magnetic fields. The composition of the ejecta from each event determines the temporal evolution of the r-process abundances during the \"chemical\" evolution of the Galaxy. Stellar r-process abundance observations, have provided insights into, and constraints on the frequency of and conditions in the responsible stellar production sites. These observations, increasingly more precise due to improved experimental atomic data and high resolution observations, have been particularly important in defining the heavy element abundance patterns of the old halo stars, and the nature of the earliest nucleosynthesis in our Galaxy. Combining new results and important breakthroughs in the related nuclear, atomic and astronomical fields of science, this review attempts to provide an answer to the question \"How Were the Elements from Iron to Uranium Made?\" (Abridged)",
  "revisions": [
    {
      "version": "v1",
      "updated": "2019-01-05T13:08:05.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "rapid neutron capture process",
      "heaviest elements",
      "nucleosynthesis path runs close",
      "stellar r-process abundance observations",
      "heavy element abundance patterns"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 85,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}