Initial mass function (IMF) is one of the most important
parameters in stellar astrophysics. However, it is not
well known. Recently there was a conference totally devoted
to this subject.
Many authors show that IMF is different in various
stellar clusters, galaxies etc.
the authors make a very important note.
They demonstrate that the accretion rate onto
newborn stars in the Trapezium Cluster is systematically smaller than in the Taurus-Auriga association.
They link this fact with accretion disk evaporation by already formed massive stars. It means that in rich stellar clusters we can expect to find more low-mass stars and brown dwarfs than in clusters with smaller number of massive OB-stars.
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