2006ApJ...653.1480W

The nature of far-infrared dust emission toward main-sequence stars, whether interstellar or circumstellar, can be deduced from submillimeter photometry. We present JCMT/SCUBA flux measurements at 850 µm toward eight stars with large photospheric excesses at 60-100 µm. Five sources were detected at 3 σ or greater significance and one was marginally detected at 2.5 σ. The inferred dust masses and temperatures range from 0.033 to 0.24 M_⊕and 43-65 K, respectively. The frequency behavior of the opacity, τ_ν∝ν^β, is relatively shallow, β<1. These dust properties are characteristic of circumstellar material, most likely the debris from planetesimal collisions. The two nondetections have lower temperatures, 35-8 K, and steeper opacity indices, β>1.5, that are more typical of interstellar cirrus. The confirmed disks all have inferred diameters ≳2", most lie near the upper envelope of the debris disk mass distribution, and four are bright enough to be feasible for high-resolution imaging.