The Lifetime Probability Tag Measurement of Rb using the SLD
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چکیده
We present a new measurement of R~ = r~o+*z/rZ04~a~.0.S 'sing a lifetime double tag on 150k hadronic 2° events collected from the SLD 1993 and 1994 runs. The method utilizes the high precision 3-D position measurements provided by the CCD vertex detector and-... .. the small stable SLC beams to obtain a 6 hemisphere tagging efficiency of 3170 for a purity of 94Yo. The ~-hemisphere tagging efficiency is measured from the data reducing dependence on the B-decay model and detector simulation. We obtain a result of Rb = 0.2171 +0.0040stat~st~ca[ *0.00373ySten.tic +0.0023RC.
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