Enrichment of the Dust-to-gas Mass Ratio in Bondi/jeans Accretion/cloud Systems Due to Unequal Changes in Dust and Gas Incoming Velocities
نویسنده
چکیده
The ratio of the Bondi and Jeans lengths is used to develop a cloud-accretion model that describes both an inner Bondi-type regime where gas pressure is balanced by the gravity of a central star and an outer Jeans-type regime where gas pressure is balanced by gas self-gravity. The gas density profile provided by this model makes a smooth transition from a wind-type inner solution to a Bonnor-Ebert-type outer solution. It is shown that high-velocity dust impinging on this cloud will tend to pile up due to having a different velocity profile from gas so that the dust-to-gas ratio is substantially enriched above the 1% interstellar medium (ISM) level. Subject headingg s: accretion, accretion disks — ISM: jets and outflows — MHD
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