Young stellar clusters in the Milky Way
In the last few years there has been a revolution in our knowledge of Galactic young stellar clusters. More than 1500 new candidate stellar clusters have been discovered from the 2MASS and Spitzer surveys, doubling the number of previously known Galactic stellar clusters. This opens new insights on the structure of the Milky Way, and on its current star formation rate. I will present an overview of the total number of stellar clusters known at present, showing how this number is only a small fraction of the actual number of clusters populating the Galactic Disk. Interstellar extinction strongly hampers their detection, and several issues concerning their spatial distribution remain still open, for
example the paucity of young clusters in the central 3 kpc, and the possible concentration of clusters in a ring surrounding the central bar. Stellar clusters are also excellent laboratories for testing models of stellar evolution. Various types of massive stars are identified among the members of the newly discovered young clusters (Wolf-Rayet stars, Ofpe/WN9, Blue, Red and Yellow supergiants). Estimates of their initial
masses, ages, and distances can be obtained by studying the properties of the associated clusters. I will show a few examples of multi-wavelength analysis (Infrared, Radio, and X-ray data) of a candidate clusters in the
direction of the inner Galaxy, showing as photometric and spectroscopic follow-up studies are needed in order to confirm the existence of these candidates, to analyze their stellar content and identify massive stars.
