The stellar and sub-stellar IMF of simple and composite populations

  title={The stellar and sub-stellar IMF of simple and composite populations},
  author={Pavel Kroupa and Carsten Weidner and Jan Pflamm-Altenburg and Ingo Thies and Joerg Dabringhausen and Michael Marks and Thomas Maschberger},
  journal={arXiv: Cosmology and Nongalactic Astrophysics},
The current knowledge on the stellar IMF is documented. It appears to become top-heavy when the star-formation rate density surpasses about 0.1Msun/(yr pc^3) on a pc scale and it may become increasingly bottom-heavy with increasing metallicity and in increasingly massive early-type galaxies. It declines quite steeply below about 0.07Msun with brown dwarfs (BDs) and very low mass stars having their own IMF. The most massive star of mass mmax formed in an embedded cluster with stellar mass Mecl… Expand
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