Forming the Dusty Ring in Hr 4796a
نویسندگان
چکیده
We describe planetesimal accretion calculations for the dusty ring observed in the nearby A0 star HR 4796A. Models with initial masses of 10–20 times the minimum mass solar nebula produce a ring of width 7–15 AU and height 0.3–0.6 AU at 70 AU in ∼ 10 Myr. The ring has a radial optical depth ∼ 1. These results agree with limits derived from infrared images and from the excess infrared luminosity. Subject headings: planetary systems – solar system: formation – stars: formation – stars: individual (HR 4796A) – circumstellar matter
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