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Title: Physical models of streaming instabilities in protoplanetary discs
ABSTRACT We develop simple, physically motivated models for drag-induced dust–gas streaming instabilities, which are thought to be crucial for clumping grains to form planetesimals in protoplanetary discs. The models explain, based on the physics of gaseous epicyclic motion and dust–gas drag forces, the most important features of the streaming instability and its simple generalization, the disc settling instability. Some of the key properties explained by our models include the sudden change in the growth rate of the streaming instability when the dust-to-gas mass ratio surpasses one, the slow growth rate of the streaming instability compared to the settling instability for smaller grains, and the main physical processes underlying the growth of the most unstable modes in different regimes. As well as providing helpful simplified pictures for understanding the operation of an interesting and fundamental astrophysical fluid instability, our models may prove useful for analysing simulations and developing non-linear theories of planetesimal growth in discs.  more » « less
Award ID(s):
2009234
NSF-PAR ID:
10281374
Author(s) / Creator(s):
;
Date Published:
Journal Name:
Monthly Notices of the Royal Astronomical Society
Volume:
498
Issue:
1
ISSN:
0035-8711
Page Range / eLocation ID:
1239 to 1251
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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