Ithaca College

Luke Keller, associate professor of physics, has been awarded four nights on the European Southern Observatory "Very Large Telescope" (VLT), located on a high mountain in northern Chile.

The VLT, an 8-meter diameter telescope, is one of the most sensitive astronomical instruments on Earth and time is allocated in a competitive proposal process. Keller will study the chemical composition of material orbiting young stars that he recently identified in a nearby galaxy using the Spitzer Space Telescope. The material may contain the raw materials for the formation of planets. Keller will travel to Chile in June, 2010, to conduct the observations.  

Technical Abstract: We have identified a sample of stars in the Small Magellanic Cloud (SMC) that have all the characteristics of intermediate-mass pre-main-sequence stars with proto-planetary disks (e.g. Herbig Ae/Be stars): unobscured stars with strong H-alpha emission located near start forming regions, significant near and mid-infrared excess emission, and mid-iR emission from polycyclic aromatic hydrocarbons (PAH). Since the SMC is very metal-poor relative to the Milky Way galaxy, this sample affords us an opportunity to characterize proto-planetary disks in an environment that is chemically similar to galaxies in the early universe.  We propose to use ISAAC on the VLT to gather near infrared spectra to measure the strengths and emission line profiles of Brackett-gamma and CO ro-vibrational bands in the K-band. These data will allow us to estimate the accretion activity (Br-gamma) and constrain gas dynamics and structure (CO bands) of these extra-galactic proto-planetary disks.  

Photo: The European Southern Observatory VLT telescopes. located in northern Chile.