The AU Mic Debris Disk: Far-Infrared and Submillimeter Resolved Imaging
Artikel i vetenskaplig tidskrift, 2015

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 μm. The disk is resolved at 70, 160, and 450 μm. 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 μm can be removed via corpuscular forces (i.e., the stellar wind).

stars: individual (AU Mic)

circumstellar matter

Författare

B. C. Matthews

National Research Council of Canada Herzberg

University of Victoria

G. Kennedy

University of Cambridge Institute of Astronomy

B. Sibthorpe

SRON Netherlands Institute for Space Research

W. S. Holland

University of Edinburgh

Royal Observatory

M. Booth

Pontificia Universidad Catolica de Chile

P. Kalas

SETI Institute

UC Berkeley

M. Macgregor

Harvard-Smithsonian Center for Astrophysics

D. J. Wilner

Harvard-Smithsonian Center for Astrophysics

B. Vandenbussche

KU Leuven

G. Olofsson

AlbaNova University Center

Jadl Blommaert

Flemish Institute for Technological Research

Vrije Universiteit Brussel

A. Brandeker

AlbaNova University Center

W. R. F. Dent

Atacama Large Millimeter-submillimeter Array

B. L. D. Vries

AlbaNova University Center

Stockholms universitet

J. D. Francesco

University of Victoria

National Research Council of Canada Herzberg

Malcolm Fridlund

Chalmers, Rymd- och geovetenskap, Radioastronomi och astrofysik

J. R. Graham

UC Berkeley

J. S. Greaves

University of St Andrews

A. Heras

ESTEC - European Space Research and Technology Centre

M. Hogerheijde

Leiden Observatory Research Institute

R. J. Ivison

European Southern Observatory

University of Edinburgh

E. Pantin

CNRS Centre National de la Recherche Scientifique

G.L. Pilbratt

ESTEC - European Space Research and Technology Centre

Astrophysical Journal

0004-637X (ISSN) 1538-4357 (eISSN)

Vol. 811 100- 100

Ämneskategorier

Astronomi, astrofysik och kosmologi

DOI

10.1088/0004-637X/811/2/100