Mid-Infrared Imaging of the First-Ascent Giant HD 233517

We present 10.8 and 18.2 μm images of HD 233517 (K2 III) made with the Observatory Spectrometer Camera for the Infrared on Keck II. Previous observations with a 3.8 m telescope indicated that a highly inclined disk with FWHM of 15 surrounds this star, but we find that HD 233517 is unresolved in the mid-IR at the highest resolution currently possible at these wavelengths. We measure the source to have FWHM less than 031 at 10.8 μm and less than 041 at 18.2 μm. Combined with more recent analyses and conclusions by others, HD 233517 appears to be a first-ascent giant star with spatially unresolved mid-IR dust emission.