A Dynamical Study of the Non-Star-forming Translucent Molecular Cloud MBM 16: Evidence for Shear-driven Turbulence in the Interstellar Medium
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چکیده
We present the results of a velocity correlation study of the high latitude cloud MBM16 using a fully sampled CO map, supplemented by new CO data. We find a correlation length of 0.4 pc. This is similar in size to the formaldehyde clumps described in our previous study. We associate this correlated motion with coherent structures within the turbulent flow. Such structures are generated by free shear flows. Their presence in this non-star forming cloud indicates that kinetic energy is being supplied to the internal turbulence by an external shear flow. Such large scale driving over long times is a possible solution to the dissipation problem for molecular cloud turbulence. Subject headings: ISM – Kinematics and dynamics; ISM Clouds; Turbulence
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تاریخ انتشار 1998