Program: GS-2009A-Q-65

Recently, we found a star-forming infrared loop around the young core-collapse supernova remnant G54.1+0.3 which appears to be composed of at least eleven pre-main sequence young stellar objects (YSOs). This active star formation in the loop is most likely triggered by the progenitor of the supernova in G54.1+0.3, and it is one of the most convincing examples of the induced star formation known, providing a rare opportunity to understand how young stars form and evolve in this unique condition. We propose to carry out GMOS observations of these young star candidates in the loop, which will serve as the first critical step to understand their nature via determining the exact spectral types and radial velocities. GMOS observation with slits of 1.0 arcsec using micro-shuffling mode will provide spectra sufficient for faint absorption features which can be used for spectral classification and radial velocity determination of these objects. (This proposal was accepted as queue observation of 2008B-Q-60 in the Gemini South. As of Sep. 29 2008, this proposal is in the "on holding" status, and is not expected to be carried out considering its RA of 19h30m. Therefore, we re-submit this proposal with a proper time request.)