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We present a detailed analysis of the high-angular resolution (0.''037,corresponding to 5 au) observations of the 1.25 mm continuum and $^{12}$CO$2-1$ emission from the disk around the T Tauri star AS 209. AS 209 hosts oneof the most unusual disks from the DSHARP sample, the first high angularresolution ALMA survey of disks (Andrews et al. 2018), as nearly all of theemission can be explained with concentric Gaussian rings. In particular, thedust emission consists of a series of narrow and closely spaced rings in theinner $\sim$60 au, two well-separated bright rings in the outer disk, centeredat 74 and 120 au, and at least two fainter emission features at 90 and 130 au.We model the visibilities with a parametric representation of the radialsurface brightness profile, consisting of a central core and 7 concentricGaussian rings. Recent hydro-dynamical simulations of low viscosity disks showthat super-Earth planets can produce the multiple gaps seen in AS 209millimeter continuum emission. The $^{12}$CO line emission is centrally peakedand extends out to $\sim$300 au, much farther than the millimeter dustemission. We find axisymmetric, localized deficits of CO emission around fourdistinct radii, near 45, 75, 120 and 210 au. The outermost gap is located wellbeyond the edge of the millimeter dust emission, and therefore cannot be due todust opacity and must be caused by a genuine CO surface density reduction, dueeither to chemical effects or depletion of the overall gas content.

Disk Substructures at High Angular Resolution Program (DSHARP): VIII. The Rich Ringed Substructures in the AS 209 Disk