Extracting |Vbc|, mc and mb from Inclusive D and B Decays
نویسنده
چکیده
Using recent results for nonperturbative contributions to the B and D meson inclusive semileptonic widths, a model independent extraction of |Vbc|, mc and mb is made from the experimentally measured B and D lifetimes and semileptonic branching ratios. Constraining the parameters of the HQET at O(1/mQ) by the D semileptonic width, |Vbc| is found to lie in the range .040 < |Vbc| < 0.057. The c and b quark masses are not well constrained due to uncertainty in the relevant scale of αs. These results assume the validity of perturbative QCD at the low scales relevant to semileptonic charm decay. Without making this assumption, somewhat less stringent bounds on Vbc from B decay alone may be obtained. UCSD/PTH 93-25 UTPT 93-21 CMU-HEP 93-13 DOE-ER/40682-37 Revised version, October 1993
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تاریخ انتشار 1993