  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.
