AAS 199th meeting, Washington, DC, January 2002
Session 92. Circumstellar Material and Atmospheres: Cooler
Display, Wednesday, January 9, 2002, 9:20am-6:30pm, Exhibit Hall

## [92.02] High-resolution Imaging of the Disk around \beta Pictoris at \lambda = 8.8, 12.5, and 17.9 \mum

Z. Wahhaj, D.W. Koerner (University of Pennsylvania), M.W. Werner (Jet Propulsion Laboratory), D.E. Backman (Franklin & Marshall College)

We present Keck mid-infrared observations of the disk around \beta Pictoris. Extended emission is evident in images obtained with the MIRLIN camera at 12.5 and 17.9 \mum. Emission is unresolved at 8.8 \mum. At 17.9 \mum, the disk is detected out to a distance of 5'' (100 AU) from the star. Interior to this, the SW lobe is wider than the NE lobe, and the long axis of isophotal contours rotates in a manner consistent with the warp detected at larger stellocentric distances in scattered-light images. At 12.5 \mum, emission displays a brightness asymmetry similar to that detected by earlier 10 \mum measurements. We refine estimates of the radial disk properties with the aid of image simulations from a 3-D disk model.