We present models of the inner region of the circumstellar disk of RY Tau which aim to explain our near-infrared ( K -band : 2.1 \mu m ) interferometric observations while remaining consistent with the optical to near-infrared portions of the spectral energy distribution .
Our sub-milliarcsecond resolution CHARA Array observations are supplemented with shorter baseline , archival data from PTI , KI and VLTI/GRAVITY and modeled using an axisymmetric Monte Carlo radiative transfer code .
The K -band visibilities are well-fit by models incorporating a central star illuminating a disk with an inner edge shaped by dust sublimation at 0.210 \pm 0.005 au , assuming a viewing geometry adopted from millimeter interferometry ( 65 ^ { \circ } inclined with a disk major axis position angle of 23 ^ { \circ } ) .
This sublimation radius is consistent with that expected of Silicate grains with a maximum size of 0.36 - 0.40 \mu m contributing to the opacity and is an order of magnitude further from the star than the theoretical magnetospheric truncation radius .
The visibilities on the longest baselines probed by CHARA indicate that we lack a clear line-of-sight to the stellar photosphere .
Instead , our analysis shows that the central star is occulted by the disk surface layers close to the sublimation rim .
While we do not see direct evidence of temporal variability in our multi-epoch CHARA observations , we suggest the aperiodic photometric variability of RY Tau is likely related temporal and/or azimuthal variations in the structure of the disk surface layers .