{
  "id": "1908.10952",
  "version": "v1",
  "published": "2019-08-28T21:35:18.000Z",
  "updated": "2019-08-28T21:35:18.000Z",
  "title": "Masses and Implications for Ages of Low-Mass Pre-Main Sequence Stars in Taurus and Ophiuchus",
  "authors": [
    "M. Simon",
    "S. Guilloteau",
    "Tracy L. Beck",
    "E. Chappilon",
    "E. Di Folco A. Dutrey",
    "Gregory A. Feiden",
    "N. Grosso",
    "L. Prato",
    "Gail. H. Schaefer"
  ],
  "comment": "Ap.J. to be published",
  "categories": [
    "astro-ph.SR",
    "astro-ph.GA"
  ],
  "abstract": "The accuracy of masses of pre-main sequence (PMS) stars derived from their locations on the Hertzsprung-Russell Diagram (HRD) can be tested by comparison with accurate and precise masses determined independently. We present 29 single stars in the Taurus star-forming region (SFR) and 3 in the Ophiuchus SFR with masses measured dynamically to a precision of at least $10 \\%$. Our results include 9 updated mass determinations and 3 that have not had their dynamical masses published before. This list of stars with fundamental, dynamical masses, M$_{dyn}$, is drawn from a larger list of 39 targets in the Taurus SFR and 6 in the Ophiuchus SFR. Placing the stars with accurate and precise dynamical masses on HRDs that do not include internal magnetic fields underestimates the mass compared to M$_{dyn}$ by about $30 \\%$. Placing them on an HRD that does include magnetic fields yields mass estimates in much better agreement with M$_{dyn}$, with an average difference between M$_{dyn}$ and the estimated track mass of $0.01\\pm0.02$~\\msun. The ages of the stars, 3--10 MY on tracks that include magnetic fields, is older than the 1--3 MY indicated by the non-magnetic models. The older ages of T Tauri stars predicted by the magnetic models increase the time available for evolution of their disks and formation of the giant gas exoplanets. The agreement between our M$_{dyn}$ values and the masses on the magnetic field tracks provides indirect support for these older ages.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2019-08-28T21:35:18.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "low-mass pre-main sequence stars",
      "magnetic fields yields mass estimates",
      "dynamical masses",
      "older ages"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 0,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}