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arXiv · 1105.4574

Semileptonic width ratios among beauty hadrons

I. I. Bigi·Th. Mannel·N. Uraltsev
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Abstract

We present predictions based on the heavy quark expansion in QCD. We find SU(3) breaking in B mesons suppressed in the framework of the HQE. B_s is expected to have the semileptonic width about 1% lower and Lambda_b about 3% higher when compared to Gamma_{sl}(B_d). The largest partial-rate preasymptotic effect is Pauli interference in the b-->u ell nu channel in Lambda_b, about +10%. We point out that the Omega_b semileptonic width is expected not to exceed that of B_d and may turn out to be the smallest among stable b hadrons despite the large mass. The underlying differences with phase-space models are briefly addressed through the heavy mass expansion.

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I. I. Bigi, Th. Mannel, N. Uraltsev. 2011-05-23. Semileptonic width ratios among beauty hadrons. https://doi.org/10.1007/jhep09(2011)012

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