{
  "id": "1703.09839",
  "version": "v1",
  "published": "2017-03-28T23:35:40.000Z",
  "updated": "2017-03-28T23:35:40.000Z",
  "title": "The earliest phases of high-mass star formation, as seen in NGC 6334 by \\emph{Herschel}",
  "authors": [
    "J. Tigé",
    "F. Motte",
    "D. Russeil",
    "A. Zavagno",
    "M. Hennemann",
    "N. Schneider",
    "T. Hill",
    "Q. Nguyen Luong",
    "J. Di Francesco",
    "S. Bontemps",
    "F. Louvet",
    "P. Didelon",
    "V. Konyves",
    "Ph. André",
    "G. Leuleu",
    "J. Bardagi",
    "L. D. Anderson",
    "D. Arzoumanian",
    "M. Benedettini",
    "J. -P. Bernard",
    "D. Elia",
    "M. Figueira",
    "J. Kirk",
    "P. G. Martin",
    "V. Minier",
    "S. Molinari",
    "T. Nony",
    "P. Persi",
    "S. Pezzuto",
    "D. Polychroni",
    "T. Rayner",
    "A. Rivera-Ingraham",
    "H. Roussel",
    "K. Rygl",
    "L. Spinoglio",
    "G. J. White"
  ],
  "comment": "36 pages, 14 figures, accepted by A&A. Complete appendix could be requested to F. Motte",
  "categories": [
    "astro-ph.GA",
    "astro-ph.SR"
  ],
  "abstract": "To constrain models of high-mass star formation, the Herschel/HOBYS KP aims at discovering massive dense cores (MDCs) able to host the high-mass analogs of low-mass prestellar cores, which have been searched for over the past decade. We here focus on NGC6334, one of the best-studied HOBYS molecular cloud complexes. We used Herschel PACS and SPIRE 70-500mu images of the NGC6334 complex complemented with (sub)millimeter and mid-infrared data. We built a complete procedure to extract ~0.1 pc dense cores with the getsources software, which simultaneously measures their far-infrared to millimeter fluxes. We carefully estimated the temperatures and masses of these dense cores from their SEDs. A cross-correlation with high-mass star formation signposts suggests a mass threshold of 75Msun for MDCs in NGC6334. MDCs have temperatures of 9.5-40K, masses of 75-1000Msun, and densities of 10^5-10^8cm-3. Their mid-IR emission is used to separate 6 IR-bright and 10 IR-quiet protostellar MDCs while their 70mu emission strength, with respect to fitted SEDs, helps identify 16 starless MDC candidates. The ability of the latter to host high-mass prestellar cores is investigated here and remains questionable. An increase in mass and density from the starless to the IR-quiet and IR-bright phases suggests that the protostars and MDCs simultaneously grow in mass. The statistical lifetimes of the high-mass prestellar and protostellar core phases, estimated to be 1-7x10^4yr and at most 3x10^5yr respectively, suggest a dynamical scenario of high-mass star formation. The present study provides good mass estimates for a statistically significant sample, covering the earliest phases of high-mass star formation. High-mass prestellar cores may not exist in NGC6334, favoring a scenario presented here, which simultaneously forms clouds and high-mass protostars.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2017-03-28T23:35:40.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "earliest phases",
      "dense cores",
      "host high-mass prestellar cores",
      "best-studied hobys molecular cloud complexes",
      "high-mass star formation signposts"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 36,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}