[Previous] | [Session 66] | [Next]
D.J. Wilner, P.T.P. Ho, M.J. Holman (SAO)
We present images of Vega obtained with the IRAM Plateau de Bure interferometer at 1.3 millimeters with 2.5 arcsecond (20 AU) resolution. Vega was the first main-sequence star other than the Sun found to exhibit infrared emission in excess of that predicted for the stellar photosphere, a common phenomenon now attributed to dusty debris in the circumstellar environment. The new high resolution 1.3 millimeter observations clearly detect the stellar photosphere together with two dust emission peaks, one offset to the northeast and the other offset to the southwest. These offset emission peaks are consistent with the barely resolved structure visible in previous submillimeter images, and they account for a large fraction of the dust emission from the Vega system. We explore the possibility that these emission peaks correspond to concentrations of dust trapped in the mean motion resonances associated with an orbiting planet. Even a small planet may develop substantial localized dust concentrations as dust spiraling starward is temporarily trapped. A variety of asymmetries are possible with such resonances, and the millimeter data offer a number of new constraints, including the dust clump spacings, intensities, and spatial extents.
The author(s) of this abstract have provided an email address for comments about the abstract: dwilner@cfa.harvard.edu