Improved Measurement of B D ! and the Pseudoscalar Decay Constant fD
نویسندگان
چکیده
We extract a relatively precise value for the decay constant of the D+ meson by measuring B(D+ → μνμ) = (4.45± 0.67 −0.36)× 10−4 using 280 pb−1 of data taken on the ψ(3770) resonance with the CLEO-c detector. We find fD+ = (223±16+7 −9) MeV . We also set a 90% confidence upper limit on B(D+ → e+ν) < 2.4× 10−5. ∗Submitted to the XXII International Symposium on Lepton and Photon Interactions at High Energies, June 30-July 5, 2005, Uppsala, Sweden
منابع مشابه
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تاریخ انتشار 2005