Near‐Infrared Interferometric Measurements of Herbig Ae/Be Stars

We have observed the Herbig Ae/Be sources AB Aur, VV Ser, V1685 Cyg (BD+404124), AS 442, and MWC 1080 with the Palomar Testbed Interferometer, obtainingthe longest baseline near-IR interferometric observations of this class ofobjects. All of the sources are resolved at 2.2 microns with angular sizescales generally <5 mas, consistent with the only previous near-IRinterferometric measurements of Herbig Ae/Be stars by Millan-Gabet andcollaborators. We determine the angular size scales and orientations predictedby uniform disk, Gaussian, ring, and accretion disk models. Although it isdifficult to distinguish different radial distributions, we are able to placefirm constraints on the inclinations of these models, and our measurements arethe first that show evidence for significantly inclined morphologies. Inaddition, the derived angular sizes for the early type Herbig Be stars in oursample, V1685 Cyg and MWC 1080, agree reasonably well with those predicted bythe face-on accretion disk models used by Hillenbrand and collaborators toexplain observed spectral energy distributions. In contrast, our data for thelater-type sources AB Aur, VV Ser, and AS 442 are somewhat inconsistent withthese models, and may be explained better through the puffed-up inner diskmodels of Dullemond and collaborators.Comment: 40 pages, 11 figures. Accepted for publication in Ap