Isgur - Wise Function for Λ b → Λ c in B - S Approach
نویسندگان
چکیده
In the heavy quark limit, the heavy baryon Λ Q (Q=b or c) can be regarded as composed of a heavy quark and a scalar light diquark which has good spin and flavor quantum numbers. Based on this picture we establish the Bethe-Salpeter (B-S) equation for Λ Q in the leading order of 1/m Q expansion. With the kernel containing both the scalar confinement and one-gluon-exchange terms we solve the B-S equation numerically. The Isgur-Wise function for Λ b → Λ c is obtained numerically from our model. Comparison with other model calculations are also presented. It seems that the Isgur-Wise function for Λ b → Λ c drops faster than that for B → D. The differential and total decay widths for Λ b → Λ c l¯ ν are given in the limit m b,c → ∞.
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