Letter to the Editor

First HARPSpol discoveries of magnetic fields in massive stars^⋆

¹ LESIA-Observatoire de Paris, CNRS, UPMC Univ., Univ. Paris-Diderot, 5 place Jules Janssen, 92195 Meudon Principal Cedex, France
e-mail: evelyne.alecian@obspm.fr
² Department of Physics and Astronomy, Uppsala University, Box 516, 751 20 Uppsala, Sweden
³ Dept. of Physics, Royal Military College of Canada, PO Box 17000, Stn Forces, Kingston K7K 7B4, Canada
⁴ Astronomical Institute Anton Pannekoek, University of Amsterdam, Science Park 904, 1098XH Amsterdam, The Netherlands
⁵ Laboratoire d’Astrophysique de Marseille, Traverse du Siphon, BP8-13376, Marseille Cedex 12, France
⁶ Instituut voor Sterrenkunde, Katholieke Universiteit Leuven, Celestijnenlaan 200 D, 3001 Leuven, Belgium
⁷ Department of Geology and Astronomy, West Chester University, West Chester, PA 19383, USA
⁸ FNRS-Institut d’Astrophysique et de Géophysique, Université de Liège, Allée du 6 Août 17, Bat B5c, 4000 Liège, Belgium
⁹ Department of Physics and Astronomy, University of Delaware, Newark, DE 19716, USA
¹⁰ European Organisation for Astronomical Research in the Southern Hemisphere, Casilla 19001, Santiago 19, Chile
¹¹ Dept. of Astronomy, University of Wisconsin-Madison, 475 N. Charter Street, Madison WI 53706-1582, USA
¹² Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218, USA
¹³ Institut für Astronomie, Universität Wien, Türkenschanzstrasse 17, 1180 Wien, Austria

Received: 28 October 2011
Accepted: 10 November 2011

Abstract

In the framework of the Magnetism in Massive Stars (MiMeS) project, a HARPSpol Large Program at the 3.6m-ESO telescope has recently started to collect high-resolution spectropolarimetric data of a large number of Southern massive OB stars in the field of the Galaxy and in many young clusters and associations. We report on the first discoveries of magnetic fields in two massive stars with HARPSpol – HD 130807 and HD 122451, and confirm the presence of a magnetic field at the surface of HD 105382 that was previously observed with a low spectral resolution device. The longitudinal magnetic field measurements strongly vary for HD 130807 from  ~–100 G to  ~700  G. Those of HD 122451 and HD 105382 are less variable with values ranging from  ~–40 to –80 G, and from  ~–300 to –600 G, respectively. The discovery and confirmation of three new magnetic massive stars, including at least two He-weak stars, is an important contribution to one of MiMeS objectives: the understanding of the origin of magnetic fields in massive stars and their impact on stellar structure and evolution.