THE INTERPLAY OF TURBULENCE AND MAGNETIC FIELDS IN STAR-FORMING REGIONS: SIMULATIONS AND OBSERVATIONS

被引:15
作者
Kirk, Helen [1 ,2 ]
Johnstone, Doug [1 ,2 ]
Basu, Shantanu [3 ]
机构
[1] Univ Victoria, Dept Phys & Astron, Victoria, BC V8P 1A1, Canada
[2] Natl Res Council Canada, Herzberg Inst Astrophys, Victoria, BC V9E 2E7, Canada
[3] Univ Western Ontario, Dept Phys & Astron, London, ON N6A 3K7, Canada
关键词
ISM: individual (Perseus); ISM: structure; magnetic fields; stars: formation; turbulence; NONAXISYMMETRIC PROTOSTELLAR CORES; PERSEUS MOLECULAR CLOUD; DENSE CORES; AMBIPOLAR DIFFUSION; UNBIASED SUBMILLIMETER; MIDINFRARED SURVEYS; NONLINEAR FLOWS; LARGE-SCALE; FRAGMENTATION; COLLAPSE;
D O I
10.1088/0004-637X/699/2/1433
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
We analyze a suite of thin-sheet magnetohydrodynamical simulations based on the formulation of Basu, Ciolek, Dapp, and 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 similar to 1 pc) to match that observed across extinction regions in Perseus. Generally, the simulated core (similar to 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.
引用
收藏
页码:1433 / 1453
页数:21
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