Mass Accretion Rates in the Carina Nebula: the Case of Trumpler 14

Planet formation theories are bound to comply with the current paradigm that protoplanetary discs appear to have lifetimes of ~3 Myr. This timescale is based on spectroscopic studies of circumstellar discs around pre-main sequence (PMS) stars located in low-density, nearby star forming regions. However, these objects do not reflect the conditions in place in the massive starburst clusters in which most stars form in the universe. Using a new robust method to identify PMS stars through their photometric excess in the Halpha band, we have studied with the WFI at the 2.2m telescope (La Silla) the PMS population in the Carina Nebula. The characterization of the population of PMS is also supported with combination of optical WFI data with SOFI (IR) and Spitzer (far IR) observations. I will present the main results of this research, focusing on the young massive cluster Trumpler 14. We found that there is a wide spread of ages (0.5 to 20 Myr) for PMS stars and that accretion from circumstellar discs continues well past 10 Myr. These results are bound to have important implications for theories of protoplanetary disc evolution and of star clusters formation in general