{
  "id": "1602.01649",
  "version": "v1",
  "published": "2016-02-04T12:01:46.000Z",
  "updated": "2016-02-04T12:01:46.000Z",
  "title": "MUSE crowded field 3D spectroscopy of over 12,000 stars in the globular cluster NGC 6397 - I. The first spectroscopic HRD of a globular cluster",
  "authors": [
    "Tim-Oliver Husser",
    "Sebastian Kamann",
    "Stefan Dreizler",
    "Martin Wendt",
    "Nina Wulff",
    "Roland Bacon",
    "Lutz Wisotzki",
    "Jarle Brinchmann",
    "Peter M. Weilbacher",
    "Martin M. Roth",
    "Ana Monreal-Ibero"
  ],
  "comment": "14 pages, 16 figures, 3 tables, resubmitted to A&A after all referee comments have been addressed, data available on http://muse-vlt.eu/science/",
  "categories": [
    "astro-ph.SR"
  ],
  "abstract": "Aims. We demonstrate the high multiplex advantage of crowded field 3D spectroscopy using the new integral field spectrograph MUSE by means of a spectroscopic analysis of more than 12,000 individual stars in the globular cluster NGC 6397. Methods. The stars are deblended with a PSF fitting technique, using a photometric reference catalogue from HST as prior, including relative positions and brightnesses. This catalogue is also used for a first analysis of the extracted spectra, followed by an automatic in-depth analysis using a full-spectrum fitting method based on a large grid of PHOENIX spectra. Results. With 18,932 spectra from 12,307 stars in NGC 6397 we have analysed the largest sample so far available for a single globular cluster. We derived a mean radial velocity of vrad=17.84+-0.07 km/s and a mean metallicity of [Fe/H]=-2.120+-0.002, with the latter seemingly varying with temperature for stars on the RGB. We determine T_eff and [Fe/H] from the spectra, and log g from HST photometry. This is the first very comprehensive HRD for a globular cluster based on the analysis of several thousands of stellar spectra. Furthermore, two interesting objects were identified with one being a post-AGB star and the other a possible millisecond-pulsar companion.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2016-02-04T12:01:46.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "muse crowded field 3d spectroscopy",
      "globular cluster ngc",
      "first spectroscopic hrd"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 14,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}