Geometry, Kinematics, and Magnetization of Simulated Prestellar Cores
Abstract
We utilize the more than 100 gravitationally bound dense cores formed in our three-dimensional, turbulent MHD simulations reported in Chen & Ostriker to analyze structural, kinematic, and magnetic properties of prestellar cores. Our statistical results disagree with the classical theory of star formation in which cores evolve to be oblate with magnetic fields parallel to the minor axes. Instead, we find that cores are generally triaxial, although the core-scale magnetic field is still preferentially most parallel to the core’s minor axis and most perpendicular to the major axis. The internal and external magnetic field directions are correlated, but the direction of integrated core angular momentum is misaligned with the core’s magnetic field, which is consistent with recent observations. The ratio of rotational/total kinetic and rotational/gravitational energies are independent of core size and consistent in magnitude with observations. The specific angular momentum also follows the observed relationship L/M ∝ R 3/2, indicating that rotation is acquired from ambient turbulence. With typical {E}rot}/{E}K∼ 0.1, rotation is not the dominant motion when cores collapse.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- September 2018
- DOI:
- 10.3847/1538-4357/aad905
- arXiv:
- arXiv:1808.02483
- Bibcode:
- 2018ApJ...865...34C
- Keywords:
-
- magnetohydrodynamics: MHD;
- stars: formation;
- turbulence;
- Astrophysics - Solar and Stellar Astrophysics;
- Astrophysics - Astrophysics of Galaxies
- E-Print:
- 15 pages, 13 figures, accepted for publication in ApJ