Star formation in the local group - NGC3603

This sub-program will showcase the multi-object spectroscopy capabilities of NIRSpec for stellar studies. We will obtain medium- and high-resolution spectroscopy of hundreds of known pre-main sequence (PMS) stars of different ages, hosted in massive starburst clusters located in different environments (metallicity) in the Local Group. The target clusters are NGC 3603 in the Galaxy, 30 Dor in the Large Magellanic Cloud, and NGC 346 in the Small Magellanic Cloud. These PMS stars have been identified photometrically as objects with strong Hα excess emission and equivalent width exceeding 10 Å, and as such appear to be actively accreting from a circumstellar disc. While for many of these objects comparison with isochrones suggests young ages of the order of a few Myr, a large number of them appear older than 20 Myr, suggesting that in these environments accretion onto PMS stars lasts longer than in small nearby Galactic star forming regions. These NIRSpec observations will allow us to obtain accurate accretion luminosities, mass accretion rates, and in-falling gas kinematics for all these stars from the analysis of several Hydrogen recombination lines (Paα, Brβ, Brγ). The ultimate scientific goal of this project is to understand the very nature of the mass accretion process, and how it depends on the mass, age, and metallicity of the individual objects. This study is unique since existing spectroscopy of PMS stars is so far limited to the solar neighborhood and no information exists for starburst clusters or for non-solar metallicity. Coordinated NIRCam parallel observations in the periphery of the same star-forming regions will support the primary science program: by revealing many more PMS stars of lower mass, they will considerably extend both the number of targets and the parameter space in this investigation.

This APT file covers the observations of NGC 3603 and the list of observation IDs is: FERRUIT_6101, FERRUIT_6151, FERRUIT_6152, FERRUIT_6153