We obtained low resolution (R = 100) mid-infrared (8-13 micron wavelengths)
spectra of 8 nearby young main sequence stars with the Keck 1 telescope and
Long-Wavelength Spectrometer (LWS) to search for 10 micron silicate (Si-O
stretch) emission from circumstellar dust. No stars exhibited readily apparent
emission: Spectra were then analyzed by least-squares fitting of a template
based on a spectrum of Comet Hale-Bopp. Using this technique, we were able to
constrain the level of silicate emission to a threshold ten times below what
was previously possible from space. We found one star, HD 17925, with a
spectrum statistically different from its calibrator and consistent with a
silicate emission peak of 7% of the photosphere at a wavelength of 10 microns.
Excess emission at 60 microns from this star has already been reported.Comment: 19 total pages, 5 Postscript figures, 2 tables, Late
