Measurement of the average lifetime of hadrons containing bottom quarks.
نویسندگان
چکیده
This thesis reports a measurement of the average lifetime of hadrons containing bottom quarks. It is based on data taken with the DELCO detector at the PEP e+estorage ring at a center of mass energy of 29 GeV. The decays of hadrons containing bottom quarks are tagged in hadronic events by the presence of electrons with a large component of momentum transverse to the event axis. Such electrons are identified in the DELCO detector by an atmospheric pressure Cerenkov counter assisted by a lead/scintillator electromagnetic shower counter. The lifetime measured is l.l7~~:$ (stat.) zE:$ (sys.) psec, consistent with previous measurements. This measurement, in conjunction with a limit on the non-charm branching ratio in b-decay obtained by other experiments, can be used to constrain the magnitude of the V’a element of the Kobayashi-Maskawamatrix to the range 0 042 +O.OOS +0.004 . -0.004 (stat*) -0.002 (sys.), where the errors reflect the uncertainty on rb only and not the uncertainties in the calculations which relate the b-lifetime and the element of the Kobayashi-Maskawamatrix.
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ورودعنوان ژورنال:
- Physical review. D, Particles and fields
دوره 37 1 شماره
صفحات -
تاریخ انتشار 1988