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arXiv · 1304.3363

On the B*' --> B transition

Benoît Blossier·John Bulava·Michael Donnellan·Antoine Gérardin
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Abstract

We present a first Nf=2 lattice estimate of the hadronic coupling g_12 which parametrises the strong decay of a radially excited B* meson into the ground state B meson at zero recoil. We work in the static limit of Heavy Quark Effective Theory (HQET) and solve a Generalised Eigenvalue Problem (GEVP), which is necessary for the extraction of excited state properties. After an extrapolation to the continuum limit and a check of the pion mass dependence, we obtain g_12 = -0.17(4).

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Benoît Blossier, John Bulava, Michael Donnellan, Antoine Gérardin. 2013-07-26. On the B*' --> B transition. https://doi.org/10.1103/physrevd.87.094518

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