%0 Journal Article
%T Resolved Multifrequency Radio Observations of GG Tau
%A Sean M. Andrews
%A Claire J. Chandler
%A Andrea Isella
%A Tilman Birnstiel
%A Katherine A. Rosenfeld
%A David J. Wilner
%A Laura M. Perez
%A Luca Ricci
%A John M. Carpenter
%A Nuria Calvet
%A Stuartt A. Corder
%A Adam T. Deller
%A Cornelis P. Dullemond
%A Jane S. Greaves
%A Robert J. Harris
%A Thomas Henning
%A Woojin Kwon
%A Joseph Lazio
%A Hendrik Linz
%A Lee G. Mundy
%A Anneila I. Sargent
%A Shaye Storm
%A Leonardo Testi
%J Physics
%D 2014
%I arXiv
%R 10.1088/0004-637X/787/2/148
%X We present sub-arcsecond resolution observations of continuum emission associated with the GG Tau quadruple star system at wavelengths of 1.3, 2.8, 7.3, and 50 mm. These data confirm that the GG Tau A binary is encircled by a circumbinary ring at a radius of 235 AU with a FWHM width of ~60 AU. We find no clear evidence for a radial gradient in the spectral shape of the ring, suggesting that the particle size distribution is spatially homogeneous on angular scales of ~0.1". A central point source, likely associated with the primary component (GG Tau Aa), exhibits a composite spectrum from dust and free-free emission. Faint emission at 7.3 mm is observed toward the low-mass star GG Tau Ba, although its origin remains uncertain. Using these measurements of the resolved, multifrequency emission structure of the GG Tau A system, models of the far-infrared to radio spectrum are developed to place constraints on the grain size distribution and dust mass in the circumbinary ring. The non-negligible curvature present in the ring spectrum implies a maximum particle size of 1-10 mm, although we are unable to place strong constraints on the distribution shape. The corresponding dust mass is 30-300 M_earth, at a temperature of 20-30 K. We discuss how this significant concentration of relatively large particles in a narrow ring at a large radius might be produced in a local region of higher gas pressures (i.e., a particle "trap") located near the inner edge of the circumbinary disk.
%U http://arxiv.org/abs/1404.5652v1