G. Abbiendi et al., Measurement of vertical bar V-cb vertical bar using (B)over-bar(0)-> D*(+)l(-)(nu)over-bar decays, PHYS LETT B, 482(1-3), 2000, pp. 15-30
The magnitude of the Cabibbo-Kobayashi-Maskawa matrix element V-cb has been
measured using (B) over bar(0) --> D*(+)l(-)(v) over bar decays recorded o
n the Z(0) peak using the OPAL detector at LEP. The D*(+) --> D(0)pi(+) dec
ays were reconstructed both in the particular decay modes D*(+) --> D(0)pi(
+) and D*(+) --> D(0)pi(+)pi(0) and via an inclusive technique. The product
of \V-cb\ and the decay form factor of the (B) over bar(0) --> D*(+)l(-)(v
) over bar transition at zero recoil F(1) was measured to be F(1)\V-cb\ = (
37.1 +/- 1.0 +/- 2.0) x 10(-3), where the uncertainties are statistical and
systematic respectively. By using Heavy Quark Effective Theory calculation
s for F(1), a value of
\V-cb\ = (40.7 +/- 1.1 +/- 2.2 +/- 1.6) x 10(-3)
was obtained. where the third error is due to theoretical uncertainties in
the value of F(1). The branching ratio Br((B) over bar(0) --> D*(+)l(-)(v)
over bar) was also measured to be (5.26 +/- 0.20 +/- 0.46)%. (C) 2000 Publi
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