MHD Turbulence in Star-Forming Regions and the Interstellar Medium

摘要: MHD turbulence plays a central role in the physics of star-forming molecular clouds and interstellar medium. must be driven to account for observed supersonic motions clouds, as even strongly magnetized decays quickly. Driven can globally support gravitationally unstable regions, but local collapse inevitably occurs. Differences strength driving gas density may explain very different rates star formation galaxies. Two types comparisons observations are reviewed. First, use wavelet transform methods suggests that comes from scales larger than clouds. Second, comparison simulated spectral cubes models real Larson’s mass-size relationship is an observational artifact. The mechanism likely combination field supernovae sections galactic disks, magnetorotational instabilities outer disks lowsurface brightness Supernova-driven has broad range pressures with roughly log-normal distribution. High-pressure, cold regions formed absence selfgravity.