A highly abnormal massive star mass function in the Orion Nebula cluster and the dynamical decay of trapezium systems

  title={A highly abnormal massive star mass function in the Orion Nebula cluster and the dynamical decay of trapezium systems},
  author={Jan Pflamm-Altenburg and Pavel Kroupa},
  journal={Monthly Notices of the Royal Astronomical Society},
The Orion Nebula cluster (ONC) appears to be unusual on two grounds: the observed constellation of the OB stars of the entire ONC and its Trapezium at its centre implies a time-scale problem given the age of the Trapezium, and an initial mass function (IMF) problem for the whole OB star population in the ONC. Given the estimated crossing time of the Trapezium, it ought to have totally dynamically decayed by now. Furthermore, by combining the lower limit of the ONC mass with a standard IMF it… 

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