Mass and Magnetic Distributions in Self-gravitating Super-Alfvénic Turbulence with Adaptive Mesh Refinement
Abstract
In this work, we present the mass and magnetic distributions found in a recent adaptive mesh refinement magnetohydrodynamic simulation of supersonic, super-Alfvénic, self-gravitating turbulence. Power-law tails are found in both mass density and magnetic field probability density functions, with P(ρ) vprop ρ-1.6 and P(B) vprop B -2.7. A power-law relationship is also found between magnetic field strength and density, with B vprop ρ0.5, throughout the collapsing gas. The mass distribution of gravitationally bound cores is shown to be in excellent agreement with recent observation of prestellar cores. The mass-to-flux distribution of cores is also found to be in excellent agreement with recent Zeeman splitting measurements. We also compare the relationship between velocity dispersion and density to the same cores, and find an increasing relationship between the two, with σ vprop n 0.25, also in agreement with the observations. We then estimate the potential effects of ambipolar diffusion in our cores and find that due to the weakness of the magnetic field in our simulation, the inclusion of ambipolar diffusion in our simulation will not cause significant alterations of the flow dynamics.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- April 2011
- DOI:
- 10.1088/0004-637X/731/1/59
- arXiv:
- arXiv:1008.2402
- Bibcode:
- 2011ApJ...731...59C
- Keywords:
-
- ISM: clouds;
- ISM: kinematics and dynamics;
- ISM: magnetic fields;
- magnetohydrodynamics: MHD;
- Astrophysics - Astrophysics of Galaxies
- E-Print:
- 9 pages, 10 figures (3 color). Submitted to the Astrophysical Journal