Calculation of the semileptonic decay width of the Λ b baryon
نویسنده
چکیده
We extend the approach based on the light-cone expansion and the heavy quark effective theory to the inclusive semileptonic decay of an unpolarized b-flavored hadron. It is applied to calculate the semileptonic decay width of the Λb baryon and its ratio to that of the B meson. We obtain ΓSL(Λb) = 51 ± 9 |Vcb| 2ps−1 and ΓSL(Λb)/ΓSL(B) = 1.052 ± 0.006. From the latter, the semileptonic branching fraction for Λb is predicted to be (8.7 ± 0.7)%.
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