AIP Calendar


External Colloquium | Mario Guarcello (INAF | O. Palermo)

Title: "Galactic superstar clusters: a bridge to starburst conditions"

With a mass in excess of 10000 solar masses, the very few superstar clusters known in the Milky Way represent the most accessible examples of starburst regions, which are very rare in our Galaxy today, but common in galaxies experiencing epochs of intense star formation. These regions, which are characterized by very high stellar density and are dominated by a rich and compact ensemble of massive stars that produce an environment dominated by energetic radiation and particles, are typically observed through large optical extinctions and lie at large distances from the Sun. Despite these observational challenges, superstar clusters represent unique targets to extend our knowledge of star and planets formation and stellar evolution in starburst conditions.

The EWOCS (Extended Westerlund 1 and 2 Open Clusters Survey) project has the objective of studying star formation and stellar evolution in the super massive star clusters Westerlund 1 and 2. With a distance of 4.5 kpc and 3.87 kpc, respectively, Westerlund 1 and 2 are the closest superstar clusters to the Sun, and thus the best targets to study star formation and evolution in the most energetic Galactic star forming environment known. Deep observations of these clusters can also shed light on how such supermassive clusters can assemble and evolve.

In this talk, I will present the motivations, status and the preliminary results of the EWOCS project, which is mainly based on a 1Msec Chandra/ACIS-I Large Project and a cycle 1 JWST observation of Westerlund 1, a cycle 2 JWST observation of Westerlund 2, and other data at high spatial resolution of the two clusters.

Last update: 3. May 2024