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We report on an experiment to obtain differential cross sections for K + p elastic scattering in the vicinity of the possible exotic baryon, the Z:(1900).The d~fferential cross sections are based on typically 70 000 selected events in the angular region-0.9 5 cosOi, 0.9 at each of 22 momenta from 0.865 to 2.125 GeV/c. The data are intended for use in partial-wave analysis to search for the z:.

We report on the very early time search for an optical afterglow from GRB 971227 with the Livermore Optical Transient Imaging System (LOTIS). LOTIS began imaging the 'Original' BATSE error box of GRB 971227 ∼ 14 s after the onset of gamma-ray emission. Continuous monitoring of the position throughout the evening yielded a total of 499 images (10 s integration). Analysis of these images revealed no steady optical afterglow brighter than R=12.3 ± 0.2 in any single image. Coaddition of the LOTIS images also failed to uncover transient optical emission. In particular, assuming a constant early time flux, no optical afterglow brighter than R=14.2 ± 0.2 was present within the first 1200 s and no optical afterglow brighter than R=15.0 ± 0.2 was present in the first 6.0 h. Follow up observations by other groups revealed a likely X-ray afterglow and a possible optical afterglow. Although subsequent deeper observations could not confirm a fading source, we show that these transients are not inconsistent with our present knowledge of the characteristics of GRB afterglows. We also demonstrate that with the upgraded thermoelectrically cooled CCDs, LOTIS is capable of either detecting very early time optical afterglow or placing stringent constraints on the relationship between the gamma-ray emission and the longer wavelength afterglow in relativistic blast wave models.

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