Carbon Monoxide in Disks Around Two T Tauri Stars: RY Tau & DG Tau

I present high-resolution, near infrared NIRSPEC spectra of carbon monoxide for two classical T Tauri stars: RY Tau and DG Tau. The purpose of the study is to further test whether there is a correlation between gas and dust with inclination to constrain models of dust settling and turbulence in disks. 12CO overtone and fundamental absorption lines in the 2.3 and 4.7 µm spectral region were measured, respectively. 13CO was detected for DG Tau. Rotational temperatures and column densities were calculated for each source. The ratio ~ NCO/AV was measured as a function of inclination and compared to the results presented by Rettig et al. (2006). The results for RY Tau follow the trend reported by Rettig et al. (2006). The gas to dust ratio toward DG Tau is enormously larger than that found for similar sources.