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James M. Bauer, Karen J. Meech, J. Patrick Henry (U. of Hawaii, Institute for Astronomy (UHIfA)), Carey M. Lisse, Yanga R. Fern\'andez (U. of Maryland, Dept. of Astronomy), Naoto Kobayashi (National Astronomical Observatory, Japan \& UHIfA), K. Koyama (Kyoto Univ.), R. Petre (GSFC), B. Kellet, R. Bingham (Rutherford Appleton Laboratory)
We were awarded 60k-sec of observing time on the ASCA X-ray satellite to observe 55P/Tempel-Tuttle with the Solid-state Imaging Spectrometer (SIS) near its January 17, 1998 perigee approach ( \Delta = 0.36 AU, r=1.19 AU). The SIS energy resolution for photon energies near a keV is on the order of E/\DeltaE\approx10, allowing for differentiation of single element from continuum contributions to X-ray emission, with a sufficiently strong detection. The observations were divided into three 20k-sec observation blocks on 1/19, 1/23, and 1/28. We also carried out nearly simultaneous optical exposures from the ground for the 1/23 exposure set. These observations were taken at the UH 2.2m telescope on 1/22, 1/23 and 1/24 in order to monitor dust production to examine how well this correlates with X-ray emission activity. A total of 126 30-second exposures were taken in open-filtered and in the Kron-Cousins BVRI bandpasses. During the night of the 23rd, the coma extended roughly 30'' (104 km) from the nucleus, which was within ASCA's half power diameter of 3 arcmin. We will present surface brightness plots and provide estimates of dust production rates from these images along with the ASCA data results. It is our intention to examine whether a correlation appears in our observations between dust production and content in the comet's coma and the measured X-ray flux as observations of other comets with EUVE seemed to have indicated.