Issue |
A&A
Volume 504, Number 1, September II 2009
|
|
---|---|---|
Page(s) | 109 - 113 | |
Section | Interstellar and circumstellar matter | |
DOI | https://doi.org/10.1051/0004-6361/200912120 | |
Published online | 09 July 2009 |
Protostellar collapse: rotation and disk formation
1
Zentrum für Astronomie (ZAH), Institut für Theoretische Astrophysik (ITA), Universität Heidelberg, Albert-Ueberle-Str. 2, 69120 Heidelberg, Germany e-mail: wmt@ita.uni-heidelberg.de
2
Institut für Geowissenschaften, Universität Heidelberg, Im Neuenheimer Feld 236, 69120 Heidelberg, Germany
Received:
20
March
2009
Accepted:
8
June
2009
We present some important conclusions from models of the collapse of rotating molecular cloud cores with axial symmetry, corresponding to the evolution of young stellar objects from class 0 to the beginning
of class I. There are three main findings of the calculations: (1)
the typical timescale for building up a preplanetary disk, which was
found to be of the order of one free-fall time decisively shorter
than the widely assumed timescale related to the so-called
“inside-out collapse”; (2) redistribution of angular momentum and
the accompanying dissipation of kinetic (rotational) energy causing
the growing disk to become more stable and strengthening the
intrinsic meridional circulation pattern of the accretion flow; and
(3) the origin of calcium-aluminium-rich inclusions (CAIs). Because
of the persistent equatorial outflow, material that has undergone
substantial chemical and mineralogical modifications in the hot
(900 K) interior of the protostellar core may have a good
chance of being advectively transported outward into the cooler
remote parts (
4 AU, say) of the growing disk and surviving
there until it is incorporated into a meteoritic parent body.
Key words: stars: formation / accretion, accretion disks / planetary systems: formation
© ESO, 2009
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.