The Formation of Massive Stars and Star Clusters
نویسندگان
چکیده
We model the formation of high-mass stars, specifying the accretion rate in terms of the instantaneous and final mass of the star, the ambient pressure of the star-forming region and the form of polytropic pressure support of the pre-stellar gas core. The high pressures typical of Galactic regions of massive star formation allow a 100 M⊙ star to form in ∼ 105 yr with a final accretion rate ∼ 10−3 M⊙ yr−1. By modeling protostellar evolution we predict the properties of several nearby massive protostars. We model cluster formation by applying this theory to many stars. We use the observed intensity of outflows from protoclusters to estimate the star formation rate, finding that clusters take at least several free-fall times to form; for a cluster similar to the Orion Nebula Cluster, we predict a formation timescale ∼ 1× 106 yr.
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