Turbulence in a self-gravitating molecular cloud core
  Externally driven interstellar turbulence plays an important role in shaping
the density structure in molecular clouds. Here we study the dynamical role of
internally driven turbulence in a self-gravitating molecular cloud core.
Depending on the initial conditions and evolutionary stages, we find that a
self-gravitating core in the presence of gravity-driven turbulence can undergo
constant, decelerated, and accelerated infall, and thus has various radial
velocity profiles. In the gravity-dominated central region, a higher level of
turbulence results in a lower infall velocity, a higher density, and a lower
mass accretion rate. As an important implication of this study, efficient
reconnection diffusion of magnetic fields against the gravitational drag
naturally occurs due to the gravity-driven turbulence, without invoking
externally driven turbulence.
