First Surface-resolved Results with the IOTA Imaging Interferometer: Detection of Asymmetries in AGB stars

  title={First Surface-resolved Results with the IOTA Imaging Interferometer: Detection of Asymmetries in AGB stars},
  author={Sam Ragland and Wesley A. Traub and J. P. Berger and William C. Danchi and John D. Monnier and Lee Anne Mordy Willson and Nathaniel P. Carleton and Marc G. Lacasse and Rafael Millan-Gabet and Ettore Pedretti and F. Peter Schloerb and W. D. Cotton and Charles H. Townes and Michael K. Brewer and Pierre Haguenauer and Pierre Y. Kern and Pierre Labeye and Fabien Malbet and David F. Malin and M. Pearlman and K. Perraut and Kamal Souccar and Gary Wallace},
We have measured non-zero closure phases for about 29% of our sample of 56 nearby Asymptotic Giant Branch (AGB) stars, using the 3-telescope Infrared Optical Telescope Array (IOTA) interferometer at near-infrared wavelengths (H band) and with angular resolutions in the range 5-10 milliarcseconds. These nonzero closure phases can only be generated by asymmetric brightness distributions of the target stars or their surroundings. We discuss how these results were obtained, and how they might be… Expand

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Cooperating Organizations AAS—American Astronomical Society (USA) AURA—Association of Universities for Research in Astronomy, Inc. (USA) European Astronomical Society European Optical SocietyExpand