Star Complex Formation in Differentially Rotating Superclouds
Conditions of giant molecular cloud’s complexes formation in central parts of rotating superclouds are investigated. It is shown that only in the most massive superclouds having masses M≥107 M⊙ the central density may become high enough for the rapid gas cooling and therefore for the cold core formation. The formulas for core parameters estimations are obtained. The forming cores have masses (1–4) · 106 M⊙ and equatorial radii about 300–500 pc that is very close to the star complexes parameters.So we can think that their origin is the result of action of proposed mechanism. In the rapidly cooling core the initially existing subsonic motions will become supersonic ones. This process can explane the nature of giant molecular cloud’s supersonic turbulence having the velocities up to 6–8 km · s−1 that is typical for the warm interstellar matter from wich the superclouds are formed.
KeywordsStar Formation Molecular Cloud Column Density Equatorial Radius Gravitational Instability
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