Raquel Salmeron, Trevor Ireland
Chondrite meteorites are believed to represent the building blocks of the
solar nebula, out of which our solar system formed. They are a mixture of
silicate and oxide objects (chondrules and refractory inclusions) that
experienced extremely high temperatures, set in a matrix that remained
relatively cold. The prevalence of chondrites suggests that they formed through
a very general process, closely related to stellar and planet formation,
however the nature and properties of the responsible mechanism have remained
unclear for many decades. The evidence for a hot solar nebula provided by
chondrules and refractory inclusions is, however, seemingly at odds with
astrophysical observations of forming stars. These strongly indicate that
protostellar disks - the inspiralling disks of gas and dust out of which stars
and planets form - are relatively cool, and exhibit typical temperatures that
are insufficient to melt and vapourise silicate minerals at the radial
distances sampled by chondrule-bearing meteorites in the main asteroid belt.
Here we present calculations of the dynamical and thermal structure of
protostellar disks that accelerate a wind from the disk surfaces. These winds
are commonly associated with young stellar objects and are the analogues of the
early solar system. We also present models of the processing of dust particles
in such winds, showing that these outflows are suitable sites for chondrule
formation.
View original:
http://arxiv.org/abs/1111.5917
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