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 Title: 

    The Inner Regions of Protoplanetary Disks

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 Authors:
 

    C.P. Dullemond, MPIA

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Abstract:

With the advent of infrared interferometry it has recently become possible to directly observe and spatially resolve the very inner few AU of protoplanetary disks. For disks around Herbig Ae/Be star these regions are of particular interest because of the high dust temperatures at which the dust grains drastically change their properties. It is also the location of the `puffed-up inner rim' predicted by some theories as a result of dust evaporation. Processes happening in this region affect the entire disk out to large radii and may have strong influence on the formation process of rocky planets. For T Tauri stars these regions are somewhat cooler and are likely the birthplace of earth-like planets. The same is true for the intermediate radius regions (~10 AU) of Herbig star disks. It is therefore not surprising that high-spatial-resolution observations of such disks receive a lot of attention recently. In addition to these spatially resolved observations, much can be told about the inner regions by other methods such as optical and infrared spectroscopy, polarimetry, photometric variations, X-rays etc). These allow astronomers to probe even smaller spatial scales.  I will review the observational results obtained in the last few years with infrared interferometry and high-resolution direct imaging and other means of probing the inner regions of disks. I will also discuss theoretical considerations which aim to explain these observations and make predictions.

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