Based on deep VLT/ISAAC JHK photometry , we have derived the present-day mass function of the central starburst cluster NGC 3603 YC ( Young Cluster ) As defined in Stolte et al .
2004 ( Paper I ) , we refer to the central cluster in NGC 3603 as “ NGC 3603 YC ” to avoid confusion with the extended H II region . in the giant H ii region NGC 3603 .
The effects of field contamination , individual reddening , and a possible binary contribution are investigated .
The MF slopes resulting from the different methods are compared , and lead to a surprisingly consistent cluster MF with a slope of \Gamma = -0.9 \pm 0.15 .
Analyzing different radial annuli around the cluster core , no significant change in the slope of the MF is observed .
However , mass segregation in the cluster is evidenced by the increasing depletion of the high-mass tail of the stellar mass distribution with increasing radius .
We discuss the indications of mass segregation with respect to the changes observed in the binned and cumulative stellar mass functions , and argue that the cumulative function as well as the fraction of high- to low-mass stars provide better indicators for mass segregation than the MF slope alone .
Finally , the observed mass function and starburst morphology of NGC 3603 YC is discussed in the context of massive local star-forming regions such as the Galactic Center Arches cluster , R 136/30 Dor in the LMC , and the Orion Trapezium cluster , all providing resolved templates for extragalactic star formation .
Despite the similarity in the observed MF slopes , dynamical considerations suggest that the starburst clusters do not form gravitationally bound systems over a Hubble time .
Both the environment ( gravitational potential of the Milky Way ) and the concentration of stars in the cluster core determine the dynamical stability of a dense star cluster , such that the long-term evolution of a starburst is not exclusively determined by the stellar evolution of its members , as frequently assumed for globular cluster systems .