Year: 2015
Type: article
Abstract: We present far-infrared and submillimeter maps from the Herschel Space Observatory and the James Clerk Maxwell Telescope of the debris disk host star AU Microscopii. Disk emission is detected at 70, 160, 250, 350, 450, 500, and 850 μ m. The disk is resolved at 70, 160, and 450 μ m. In addition to the planetesimal belt, we detect thermal emission from AU Mic's halo for the first time. In contrast to the scattered light images, no asymmetries are evident in the disk. The fractional luminosity of the disk is and its milimeter-grain dust mass is (±20%). We create a simple spatial model that reconciles the disk spectral energy distribution as a blackbody of 53 ± 2 K (a composite of 39 and 50 K components) and the presence of small (non-blackbody) grains which populate the extended halo. The best-fit model is consistent with the "birth ring" model explored in earlier works, i.e., an edge-on dust belt extending from 8.8 to 40 AU, but with an additional halo component with an surface density profile extending to the limits of sensitivity (140 AU). We confirm that AU Mic does not exert enough radiation force to blow out grains. For stellar mass-loss rates of 10–100 times solar, compact (zero porosity) grains can only be removed if they are very small; consistently with previous work, if the porosity is 0.9, then grains approaching 0.1 μ m can be removed via corpuscular forces (i.e., the stellar wind).
Source: The Astrophysical Journal
Authors: Brenda C. Matthews, Grant Kennedy, Bruce Sibthorpe, Wayne Holland, Mark Booth, Paul Kalas, Meredith MacGregor, David Wilner, Bart Vandenbussche, Göran Olofsson, Joris Blommaert, Alexis Brandeker, W. R. F. Dent, Bernard L. de Vries, James Di Francesco, Malcolm Fridlund, James R. Graham, Jane Greaves, Ana M. Heras, Michiel Hogerheijde, R. J. Ivison, Eric Pantin, Göran L. Pilbratt
Institutions: Herzberg Institute of Astrophysics, University of Victoria, National Research Council Canada, University of Cambridge, Space Research Organisation Netherlands, Science and Technology Facilities Council, Royal Observatory, UK Astronomy Technology Centre, University of Edinburgh, Pontificia Universidad Católica de Chile, Search for Extraterrestrial Intelligence, University of California, Berkeley, Center for Astrophysics Harvard & Smithsonian, KU Leuven, Stockholm University, AlbaNova, Vrije Universiteit Brussel, Flemish Institute for Technological Research, Atacama Large Millimeter Submillimeter Array, Leiden University, Leiden Observatory, Chalmers University of Technology, University of St Andrews, European Space Research and Technology Centre, European Southern Observatory, Centre National de la Recherche Scientifique, Commissariat à l'Énergie Atomique et aux Énergies Alternatives, Astrophysique, Instrumentation et Modélisation, Institut de Recherche sur les Lois Fondamentales de l'Univers
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: bronze
Funders: National Science Foundation, National Aeronautics and Space Administration, California Institute of Technology, UK Space Agency, Space Telescope Science Institute, Imperial College London, European Commission, Cardiff University, Centre National d’Etudes Spatiales, KU Leuven, Centre National de la Recherche Scientifique, Bundesministerium für Verkehr, Innovation und Technologie, Max-Planck-Institut für Astronomie, Canadian Space Agency, Science and Technology Facilities Council, National Astronomical Observatories, Chinese Academy of Sciences, FP7 Ideas: European Research Council
OpenAlex ID: W2185925527