Letter to the Editor

Cold dust in three massive evolved stars in the LMC ^*,**

¹ Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218, USA e-mail: mboyer@stsci.edu
² School of Physical & Geographical Sciences, Lennard-Jones Laboratories, Keele University, Staffordshire ST5 5BG, UK
³ Institut d'Astrophysique de Paris, CNRS UPR 341, 98bis, Boulevard Arago, 75014 Paris, France
⁴ Louisiana State University, Department of Physics & Astronomy, 233-A Nicholson Hall, Tower Dr., Baton Rouge, LA 70803, USA
⁵ Jodrell Bank Centre for Astrophysics, Alan Turing Building, School of Physics and Astronomy, University of Manchester, Oxford Road, Manchester M13 9PL, UK
⁶ Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT, UK
⁷ Mullard Space Science Laboratory, University College London, Holmbury St. Mary, Dorking, Surrey RH5 6NT, UK
⁸ Department of Physics and Astronomy, Iowa State University, Ames, IA, 50011, USA
⁹ Steward Observatory, University of Arizona, 933 North Cherry Ave., Tucson, AZ 85721, USA
¹⁰ CEA, Laboratoire AIM, Irfu/SAp, Orme des Merisiers, 91191 Gif-sur-Yvette, France
¹¹ National Radio Astronomy Observatory, Department of Astronomy, University of Virginia, PO Box 3818, Charlottesville, VA 22903 USA
¹² Johns Hopkins University, Department of Physics and Astronomy, Homewood Campus, Baltimore, MD 21218, USA
¹³ Department of Astronomy, Cornell University, Ithaca, NY 14853, USA

Received: 26 March 2010
Accepted: January 1900

Abstract

Massive evolved stars can produce large amounts of dust, and far-infrared (IR) data are essential for determining the contribution of cold dust to the total dust mass. Using Herschel, we search for cold dust in three very dusty massive evolved stars in the Large Magellanic Cloud: R71 is a luminous blue variable, HD 36402 is a Wolf-Rayet triple system, and IRAS05280-6910 is a red supergiant. We model the spectral energy distributions using radiative transfer codes and find that these three stars have mass-loss rates up to 10^-3  yr^-1, suggesting that high-mass stars are important contributors to the life-cycle of dust. We found far-IR excesses in two objects, but these excesses appear to be associated with ISM and star-forming regions. Cold dust (T < 100 K) may thus not be an important contributor to the dust masses of evolved stars.