{
  "id": "1209.4079",
  "version": "v1",
  "published": "2012-09-18T20:00:01.000Z",
  "updated": "2012-09-18T20:00:01.000Z",
  "title": "On the true shape of the upper end of the stellar initial mass function: The case of R136",
  "authors": [
    "Sambaran Banerjee",
    "Pavel Kroupa"
  ],
  "comment": "6 pages, 3 figures, source compatible with pdfLaTeX. Accepted for publication in Astronomy and Astrophysics",
  "categories": [
    "astro-ph.GA",
    "astro-ph.SR"
  ],
  "abstract": "Context: The shape of the stellar initial mass function (IMF) of a star cluster near its upper mass limit is a focal topic of investigation as it determines the high mass stellar content and hence the dynamics of the cluster at its embedded phase as well as during its young gas-free phase. The massive stellar content of a young cluster, however, can be substantially modified due to the dynamical ejections of the massive stars so that the present-day high-mass stellar mass function (hereafter MF) can be different than that with which the cluster is born. Aims: In the present study, we provide a preliminary estimate of this evolution of the high-mass IMF of a young cluster due to early ejections of massive stars, using the Large Magellanic Cloud massive, young cluster R136 as an example. Methods: To that end, we utilize the results of the state-of-the-art calculations by Banerjee, Kroupa & Oh (2012) comprising direct N-body computations of realistic, binary-rich, mass-segregated models of R136. In particular, these calculations provide the ejection fraction of stars as a function of stellar mass. Results: We find that if the measured IMF of R136 is granted to be canonical, as observations indicate, then the \"true\" high-mass IMF of R136 at its birth must be at least moderately top-heavy when corrected for the dynamical escape of massive stars. Conclusions: The top-heaviness of the true high-mass IMF over the observationally determined one is a general feature of massive, young clusters where the dynamical ejection of massive stars is efficient. We discuss its implications and possible improvements over our current estimate.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2012-09-18T20:00:01.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "stellar initial mass function",
      "upper end",
      "true shape",
      "young cluster",
      "high-mass stellar mass function"
    ],
    "tags": [
      "journal article"
    ],
    "publication": {
      "doi": "10.1051/0004-6361/201218972",
      "journal": "Astronomy and Astrophysics",
      "year": 2012,
      "month": "Nov",
      "volume": 547
    },
    "note": {
      "typesetting": "PDFLaTeX",
      "pages": 6,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "inspire": 1186510,
      "adsabs": "2012A&A...547A..23B"
    }
  }
}