KRUGER A.J., RICHTER M.J., CARR J.S., NAJITA J.R., DOPPMANN G.W. and SEIFAHRT A.
Abstract (from CDS):
We present findings for DG Tau B and VV CrA, two of the objects observed in our Spitzer Infrared Spectrograph (IRS) project to search for molecular absorption in edge-on disks, along with near-IR spectroscopy of the CO fundamental transitions and mid-IR imaging. While the only gas absorption seen in the Spitzer IRS spectrum toward DG Tau B is CO2, we use gas abundances and gas/ice ratios to argue that we are probing regions of the disk that have low organic molecule abundances. This implies that the rarity of detecting molecular absorption toward even edge-on disks with Spitzer IRS is a result of high dependence on the line of sight. We also argue that the disk around DG Tau B shows high amounts of grain growth and settling. For VV CrA, we use the silicate absorption feature to estimate a dust extinction, and model the disk with a spectral energy distribution fitting tool to give evidence in support of the disk geometry presented by Smith et al. where the primary disk is the main source of extinction toward the infrared companion.