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Massive c-quark contributions to semileptonic b-quark decay near threshold

Matthew Dowling·Alexey Pak
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Abstract

The decay width of b to c,c,c,l,nu has been computed as an expansion in limit (1- 3*(m_c/m_b)) << 1 with zero lepton invariant mass. Considering O(alpha_s^2) corrections to b to c,l,nu with zero invariant lepton mass, inclusion of our result is shown to rectify the disagreement between the expansions around (1-(m_c/m_b)) << 1 and m_c/m_b << 1 at smaller values.

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Matthew Dowling, Alexey Pak. 2006-11-03. Massive c-quark contributions to semileptonic b-quark decay near threshold. https://arxiv.org/abs/hep-ph/0611047

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