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arXiv · 1601.06801

A ring-like concentration of mm-sized particles in Sz 91

H. Canovas·C. Caceres·M. R. Schreiber·A. Hardy·L. Cieza·F. Ménard·A. Hales
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Abstract

Models of planet formation and disc evolution predict a variety of observables in the dust structure of protoplanetary discs. Here we present Atacama Large Millimeter/submillimeter Array (ALMA) Band-6 and Band-7 observations of the transition disc Sz\,91 showing that the continuum emission at 870$\mu$m, which is dominated by emission from large dust grains, is localized in an optically thin narrow ring. We find that most of the emission ($\sim95\%$) is concentrated in a ring located at 110 au from the central star that is only about 44 au wide. In contrast, the $^{12}\mathrm{CO}$ (2-1) emission peaks closer to the star and is detected up to $\sim488$ au from the star. The concentration of large grains in a ring-like structure while the gas disc extends much further in and further out is in qualitative agreement with predictions of hydrodynamical models of planet-disc interactions including radial drift and gas drag.

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H. Canovas, C. Caceres, M. R. Schreiber, A. Hardy, L. Cieza, F. Ménard, A. Hales. 2016-01-25. A ring-like concentration of mm-sized particles in Sz 91. https://doi.org/10.1093/mnrasl/slw006

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