Constraining the Physical Parameters of the Circumstellar Disk of χ Ophiuchi

Abstract

We present a numerical model describing a circularly symmetric gaseous disk around the Be star χ Ophiuchi. The model is constrained by long-baseline interferometric observations that are sensitive to the Hα Balmer line emission from the disk. For the first time, our interferometric observations spatially resolve the inner region of the circumstellar disk around χ Oph, and we use these results to place a constraint on the physical extent of the Hα-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.