Astronomy and Astrophysics – Astrophysics
Scientific paper
2005-08-24
Astrophys.J.635:1151-1165,2005
Astronomy and Astrophysics
Astrophysics
Submitted to ApJ
Scientific paper
10.1086/497566
We test the hypothesis that the starless cores may be gravitationally bound clouds supported largely by thermal pressure by comparing observed molecular line spectra to theoretical spectra produced by a simulation that includes hydrodynamics, radiative cooling, variable molecular abundance, and radiative transfer in a simple one-dimensional model. The results suggest that the starless cores can be divided into two categories: stable starless cores that are in approximate equilibrium and will not evolve to form protostars, and unstable pre-stellar cores that are proceeding toward gravitational collapse and the formation of protostars. The starless cores might be formed from the interstellar medium as objects at the lower end of the inertial cascade of interstellar turbulence. Additionally, we identify a thermal instability in the starless cores. Under par ticular conditions of density and mass, a core may be unstable to expansion if the density is just above the critical density for the collisional coupling of the gas and dust so that as the core expands the gas-dust coupling that cools the gas is reduced and the gas warms, further driving the expansion.
Field George
Keto Eric
No associations
LandOfFree
Dark cloud cores and gravitational decoupling from turbulent flows does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Dark cloud cores and gravitational decoupling from turbulent flows, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Dark cloud cores and gravitational decoupling from turbulent flows will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-268415