charmless semileptonic branching ratio of b hadrons
نویسنده
چکیده
We calculate the inclusive charmless semileptonic decay width of the B meson using a QCD-based approach. This approach is able to account for both dynamic and kinematic effects of nonperturbative QCD. The charmless semileptonic decay width is found to be enhanced by long-distance strong interactions by +(7± 5)% with respect to the free quark decay width. Using the resulting theoretical value for the charmless semileptonic decay width, an extraction of |Vub| is made from the measured lifetime and inclusive charmless semileptonic branching ratio of b hadrons.
منابع مشابه
UOM/NPh/HQP/00-3 UH-511-962-00 Inclusive charmless semileptonic decay of Λb and Br(b → Xulνl)
We study the inclusive charmless semileptonic decay of Λb, Λb → Xulνl, in the framework of heavy quark expansion and find that the rate is substantially enhanced by spectator effect. We obtain Br(b → Xulνl) to be 1.13× 10 −3 for |Vub| = 3.3× 10 . We discuss our result in light of the recent LEP measurements of the charmless semileptonic branching ratio where such enhancement was not taken into ...
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