Stars

Mechanics

Molecular cloud

Astronomy

Astrophysics

SPHERES

Thermodynamics

Star formation

Isothermal process

Similarity solution

Protostar

Boundary layer

Gravitational collapse

Physics

The Astrophysical Journal

view Abstract Citations (1574) References (29) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Self-similar collapse of isothermal spheres and star formation. Shu, F. H. Abstract Similarity solutions are obtained which describe the gravitational collapse of isothermal spheres that originated as gas clouds not far removed from the condition of marginal stability. It is argued that the similarity solution of Larson and Penston (1969) for the stages before core formation is physically artificial, but the gasdynamic flow subsequent to core formation exhibits self-similar properties. Similarity solutions are determined for the collapse of singular isothermal spheres, minus solutions without critical points are obtained by imposing the condition that the fluid velocities are negligible at the 'initial instant', and an expansion-wave collapse solution is evaluated. The results are illustrated with a numerical example roughly corresponding to conditions appropriate for Bok globules or...

Self-similar collapse of isothermal spheres and star formation