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arXiv · 0904.4511

The Interplay of Turbulence & Magnetic Fields in Star-Forming Regions: Simulations and Observations

Helen Kirk·Doug Johnstone·Shantanu Basu
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Abstract

We analyze a suite of thin sheet magnetohydrodynamical simulations based on the formulation of Basu, Ciolek, Dapp & Wurster. These simulations allow us to examine the observational consequences to a star-forming region of varying the input level of turbulence (between thermal and a Mach number of 4) and the initial magnetic field strength corresponding to a range of mass to flux ratios between subcritical (mu_0=0.5) and supercritical (mu_0=10). The input turbulence is allowed to decay over the duration of the simulation. We compare the measured observable quantities with those found from surveying the Perseus molecular cloud. We find that only the most turbulent of simulations (high Mach number and weak magnetic field) have sufficient large-scale velocity dispersion (at ~1 pc) to match that observed across extinction regions in Perseus. Generally, the simulated core (~0.02 pc) and line of sight velocity dispersions provide a decent match to observations. The motion between the simulated core and its local environment, however, is far too large in simulations with high large-scale velocity dispersion.

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Helen Kirk, Doug Johnstone, Shantanu Basu. 2009-04-28. The Interplay of Turbulence & Magnetic Fields in Star-Forming Regions: Simulations and Observations. https://doi.org/10.1088/0004-637x%2F699%2F2%2F1433

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