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| EPoS Contribution |
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The Luminosity Functions and Timescales of MYSOs and UCHII regions
Joseph C. Mottram University of Exeter, Exeter, UK | |
| We present the first determination of the luminosity functions of massive young stellar objects (MYSOs) and ultra-compact (UC) HII regions within the Milky Way galaxy. These are determined from the large, well-selected sample of these sources identified by the Red MSX Source (RMS) survey, which contain few if any MYSOs, which are luminous radio quiet mid-IR point sources, with L >~10^5 Lsol. This lack of high luminosity MYSOs is not seen in UCHII regions. We therefore discuss how these results compare with the various theories as to how the formation of an HII region around a young star may be inhibited or slowed. In particular, we suggest that the results presented are consistent with stellar structure calculations which suggest that massive stars may become swollen if accretion rates are high. We will also present the lifetimes of the MYSOs and UCHII region phases as a function of luminosity, calculated from the luminosity functions. | |
| Collaborators: M.G. Hoare, University of Leeds, UK S.L. Lumsden, University of Leeds, UK R.D. Oudmaijer, University of Leeds, UK J.S. Urquhart, CSIRO, Australia B. Davies, University of Leeds, UK T.J.T. Moore, Liverpool John Moores University, UK J.J. Stead, University of Leeds, UK |
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