No evidence for mass segregation in young clusters

Aims. We investigate the validity of mass segregation indicators commonly used in the analysis of young stellar clusters. Methods. We simulate observations by constructing synthetic seeing limited images of a 1000 massive clusters (10 M ) with a standard IMF and a King density distribution function. Results. We find that commonly used indicators are highly sensitive to sample incompleteness in observational data, and that radial completeness determinations do not provide satisfactory corrections, rendering the studies of radial properties highly uncertain. On the other hand, we find that under certain conditions, the global completeness can be estimated accurately, allowing for the correction of the global luminosity and mass functions of the cluster. Conclusions. We argue that there is currently no observational evidence for mass segregation in young compact clusters since there is not a robust way to differentiate between true mass segregation and sample incompleteness effects. Caution should then be exercised when interpreting results from observations as evidence for mass segregation.