Program: GS-2007A-Q-38

Title:Mid-IR sizes of YSO disks: Precision calibration using interferometry
PI:John Monnier
Co-I(s): Peter Tuthill

Abstract

We propose to measure the sizes of young stellar objects in the thermal infrared, a wavelength range which probes the region of the circumstellar disk where gas giant planets are expected to form. Previous attempts to obtain precisely calibrated imaging data with large aperture telescopes have been frustrated by unstable atmospheric seeing which affects the time-averaged PSF. To overcome this, we have implemented a novel sparse-aperture interferometry experiment to enable robust mid-IR diffraction-limited imaging. A cryogenic pupil mask has been installed in TReCS, allowing high-sensitivity (low-thermal background) aperture masking. Commissioning observations from semester 2004b have yielded the highest-fidelity images yet recovered in the mid-infrared over the spatial scale range from 0.1 - 1.0 arcseconds. These capabilities give access to many of the closest, heavily-embedded, massive YSOs. We began our TRECS survey last semester 2006B in approved Queue-scheduled observing (band 2) and here propose to continue, focusing on galactic plane objects up in first half of year.

Publications using this program's data