The Mass Ratio mc/mb in Semi-Leptonic h-Decays*
نویسنده
چکیده
The calculation of the ~23 mixing angle from semi-leptonic B-decay depends’ on the mass ratio m,/mb. The energy scales at which the running masses m, and rnb should be taken are determined once terms of order [cys . (mc/mb)] are taken into account. We give an analytic expression for the QCD correction to the decay rate to all orders in the ratio between on-shell masses. We explain how it should be modified when both masses are taken at a single common scale. Submitted to Phys. Lett. B -k Work supported by the Department of Energy, contract DE-AC03-76SF00515.
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