Circumstellar disk of {chi} Oph

The model is constrained by long-baseline interferometric observations that are sensitive to the H{alpha} Balmer line emission from the disk. For the first time, our interferometric observations spatially resolve the inner region of the circumstellar disk around {chi} Oph, and we use these results to place a constraint on the physical extent of the H{alpha}-emitting region.

We demonstrate how this in turn results in very specific constraints on the parameters that describe the variation of the gas density as a function of radial distance from the central star.