Paper: astro-ph/0511372
Date: Sat, 12 Nov 2005 01:16:33 GMT (293kb)

Title: The Evolution of the Water Distribution in a Viscous Protoplanetary Disk

Authors: Fred J. Ciesla and Jeffrey N. Cuzzi

Comments: 45 pages, 7 figures, revised for publication in Icarus
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(Abridged) Astronomical observations have shown that protoplanetary disks are
dynamic objects through which mass is transported and accreted by the central
star. Age dating of meteorite constituents shows that their creation,
evolution, and accumulation occupied several Myr, and over this time disk
properties would evolve significantly. Moreover, on this timescale, solid
particles decouple from the gas in the disk and their evolution follows a
different path. Here we present a model which tracks how the distribution of
water changes in an evolving disk as the water-bearing species experience
condensation, accretion, transport, collisional destruction, and vaporization.
Because solids are transported in a disk at different rates depending on their
sizes, the motions will lead to water being concentrated in some regions of a
disk and depleted in others. These enhancements and depletions are consistent
with the conditions needed to explain some aspects of the chemistry of
chondritic meteorites and formation of giant planets. The levels of
concentration and depletion, as well as their locations, depend strongly on the
combined effects of the gaseous disk evolution, the formation of rapidly
migrating rubble, and the growth of immobile planetesimals. We present examples
of evolution under a range of plausible assumptions and demonstrate how the
chemical evolution of the inner region of a protoplanetary disk is intimately
connected to the physical processes which occur in the outer regions.

\\ ( http://arXiv.org/abs/astro-ph/0511372 , 293kb)