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Halting Planet Migration in the Evacuated Centers of Protoplanetary Disks

Marc J. Kuchner·Myron Lecar
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Abstract

Precise Doppler searches for extrasolar planets find a surfeit of planets with orbital periods of 3-4 days, and no planets with orbital periods less than 3 days. The circumstellar distance, R_0, where small grains in a protoplanetary disk reach sublimation temperature (~1500 K) corresponds to a period of ~6 days. Interior to R_0, turbulent accretion due to magneto-rotational instability may evacuate the disk center. We suggest that planets with orbital periods of 3-4 days are so common because migrating planets halt once this evacuated region contains the sites of their exterior 2:1 Lindblad resonances.

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Marc J. Kuchner, Myron Lecar. 2002-06-14. Halting Planet Migration in the Evacuated Centers of Protoplanetary Disks. https://doi.org/10.1086/342370

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