Spectroscopic and Spectro-Astrometric Analysis of T Tauri Stars

To understand our own solar origins, we must investigate the composition of the protoplanetary disk from which the solar system formed. To infer this, we study analogs to the early solar system called T Tauri stars. These objects are low-mass, pre-main sequence stars surrounded by circumstellar disks of material from which planets are believed to form. We present high-resolution, near-infrared spectroscopic data for the T Tauri stars DR Tau and AA Tau using NIRSPEC at the Keck II telescope. For DR Tau, a spectro-astrometric analysis was performed, obtaining sub-seeing spatial information on water emission. Alongside a disk model, we constrained the viewing geometry of the disk (position angle ~140o, inclination ~13o) and the emitting region of the water emission lines (~0.056 – 0.38 AU). For AA Tau, we observed a superposition of strong water and OH absorption and emission features from two separate years, 2010 and 2014. During that time frame, AA Tau went through a dimming event, the effects of which we analyzed and used to discuss the implications for the source of the dimming event