Warm Circumbinary Dust in the Hd 98800 Quadruple Star System

HD 98800 is a 10 Myr, hierarchical quadruple with a signi cant dust component rst detected by IRAS. This dust is present in spite of the multiple stellar components [A-B, a visual pair with Sep =0.008, Aa+Ab, a single-lined spectroscopic binary with P = 262 d, and Bb+Ba, a double-lined spectroscopic binary with P = 315 d (Torres et al. 1995, ApJ, 452, 870)]. In order to study the relationship between the multiple components and the dust distribution, we have carried out a di raction-limited imaging study of this young multiple star system from 1 18.2 m with the W. M. Keck 10-m telescopes using near-IR speckle imaging with NIRC, adaptive optics imaging with K-CAM, and mid-IR imaging with OSCIR. This high spatial resolution work compliments that recently presented by Soderblom et al. (1998, ApJ, 498, 385), Gehrz et al. (1999, ApJ, 512, L55) and Low et al. (1999, ApJ, in press). The emission from HD 98800 is easily resolved between the two 0.008 components from 1 18.2 m (see Figures 1 and 2). Our measurements are the rst to resolve the system at multiple wavelengths through the silicate feature (see Figure 3).