GeminiFocus April 2015 | Page 6

Figure 2. JHK color-composite image of RCW 41 observed with GeMS at Gemini South. 1 and 2, respectively; also called “collect and collapse”); interaction with a pre-existing turbulent media (3; leading to the formation of pillars); and interaction with pre-existing clumps (4). One of the key questions in this field of research is what is the causal link between the first generation massive stars (the ones associated with the large HII regions) and the young (possibly second-generation) stars observed at the edges of HII regions? Dissecting the young clusters that formed at the edges of HII regions is therefore an important step to refine our knowledge on star-formation mechanisms. The Sharp Gemini Eye Studies of young star clusters are still limited. Young, recently formed stars in clusters are shy, and usually hide inside a heavily obscured and dense environment. High spatial resolution in the near infrared (NIR) is needed to resolve individual members and detect the fainter ones. The Gemini South telescope offers one of the most advanced adaptive optics (AO) suites currently available on a large telescope. Among these capabilities, the Gemini Multi-conjugate adaptive optics System (GeMS) delivers a uniform, almost diffractionlimited image quality at nearinfrared wavelengths over an extended field-of-view of 2 arcminutes across. Figure 3. GeMS/GSAOI (top) and SofI (bottom) images of the central part of the RCW 41 cluster observed in H-band. 4 GeMS utilizes five artificial laser guide stars, up to three natural guide stars, and multiple deformable mirrors (DMs) that are optically conjugated with the main atmospheric turbulence layers. This results GeminiFocus in an AO corrected field that is 10 to 20 times larger than previous generations of AO systems. GeMS works in conjunction with the Gemini South Adaptive Optics Imager (GSAOI), which covers an 85” × 85” field-of-view with a plate scale of about 20 milliarcseconds. This combination of new instruments is perfectly suited for young cluster studies, as it provides a uniform and unprecedented spatial resolution spanning a large portion of the young cluster’s angular extent. Back in 2013, during the GeMS