Statistical properties of star formation in molecular clouds
http://phys.org/news/2016-09-statistical-properties-star-formation-molecular.html
Stars form within the dense regions of diffuse molecular clouds, but the physical processes that determine the locations, rate, and efficiency of star formation
are poorly understood. Recent thinking envisions an approximately two-step process: first, a network of dense filaments form due to large-scale turbulence and
then fragmentation into cores occurs as gravity starts to dominate. In the dense gas the structure formation is affected by motions induced primarily by three
processes: supersonic turbulence, self-gravity, and magnetic fields, although the role of each process is still debated.
Recent research suggests that the statistical properties of the column density (for example, the numbers of cores denser than a fixed value) offer a key to
unraveling structure formation mechanisms. Computer simulations of star formation show that if the number of dense cores having any particular density value
is random, then turbulence is probably dominant, but if denser cores tend to cluster non-randomly, then gravity is probably dominant.