Structure in the Dusty Debris around Vega

Abstract

We present images of the Vega system obtained with the IRAM Plateaude Bure interferometer at a 1.3 mm wavelength with submillijanskysensitivity and ~2.5" resolution (about 20 AU). These observationsclearly detect the stellar photosphere and two dust emission peaksoffset from the star by 9.5" and 8.0" to the northeast and southwest,respectively. These offset emission peaks are consistent with thebarely resolved structure visible in previous submillimeter images,and they account for a large fraction of the dust emission. The presenceof two dust concentrations at the observed locations is plausiblyexplained by the dynamical influence of an unseen planet of a fewJupiter masses in a highly eccentric orbit that traps dust in principalmean motion resonances. Based on observations carried out with theIRAM Plateau de Bure Interferometer. IRAM is supported by the InstutNationale des Sciences de L'Univers, CNRS (France), Max-Plank-Gesellschaft(Germany), and Instituto Geográfico Nacional (Spain).