Criticality and convergence in Newtonian collapse

Details Criticality and convergence in Newtonian collapse Criticality and convergence in Newtonian collapse

2002-10-09

arxiv.org/abs/gr-qc/0210027v3

Phys.Rev. D67 (2003) 084003

Astronomy and Astrophysics

Astrophysics

General Relativity and Quantum Cosmology

15 pages, 8 figures, accepted for publication in PRD, figures 1 and 3 at lower resolution than in journal version, typos corre

Scientific paper

10.1103/PhysRevD.67.084003

We study through numerical simulation the spherical collapse of isothermal gas in Newtonian gravity. We observe a critical behavior which occurs at the threshold of gravitational instability leading to core formation. For a given initial density profile, we find a critical temperature, which is of the same order as the virial temperature of the initial configuration. For the exact critical temperature, the collapse converges to a self-similar form, the first member in Hunter's family of self-similar solutions. For a temperature close to the critical value, the collapse first approaches this critical solution. Later on, in the supercritical case, the collapse converges to another self-similar solution, which is called the Larson-Penston solution. In the subcritical case, the gas bounces and disperses to infinity. We find two scaling laws: one for the collapsed mass in the supercritical case and the other for the maximum density reached before dispersal in the subcritical case. The value of the critical exponent is measured to be $\simeq 0.11$ in the supercritical case, which agrees well with the predicted value $\simeq 0.10567$. These critical properties are quite similar to those observed in the collapse of a radiation fluid in general relativity. We study the response of the system to temperature fluctuation and discuss astrophysical implications for the insterstellar medium structure and for the star formation process. Newtonian critical behavior is important not only because it provides a simple model for general relativity but also because it is relevant for astrophysical systems such as molecular clouds.

Affiliated with

Also associated with

No associations

Rating

Criticality and convergence in Newtonian collapse 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 Criticality and convergence in Newtonian collapse, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Criticality and convergence in Newtonian collapse will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-204609