Inner Disks Around Young Stars
A wealth of evidence has accumulated over the last decade or so proving the existence of massive disks of dust and gas around some pre-main sequence stars. However, the innermost regions of these disks, where material accretes from the disk onto the star, remain poorly studied due to the lack of high-angular resolution observations. Over the past several years, I have been observing T Tauri and Herbig Ae/Be stars at milliarcsecond resolution using near infrared interferometers. This work has helped to elucidate the basic structure of inner disk regions.

In 2006 we commissioned a grism with a resolving power of 240 at the Keck Interferometer and used it to constrain gas, as well, as dust around young stars (Eisner 2007); this work was also described in this article.


A sketch of the inner disk regions from van Boekel (2007), intended to describe the observational data in Eisner (2007).

We have recently commissioned a grism with an order of magnitude higher dispersion, and are currently using it to spectrally and spatially resolve gaseous emission features at sub-AU radii around young stars. In a recent paper, we observed emission from hydrogen on scales smaller than 0.01 AU; these data provide direct constraints on the process by which gas is accretied onto the central stars (Eisner et al. 2010).


Josh Eisner; May 25, 2010