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arXiv · 1202.0454

Heavy-quark symmetries in the light of nonperturbative QCD approaches

Bruno El-Bennich·Craig D. Roberts·Mikhail A. Ivanov
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Abstract

We critically review the validity of heavy-quark spin and flavor symmetries in heavy-light decay constants, form factors and effective couplings obtained within a nonperturbative framework, the ingredients of which are all motivated by Dyson-Schwinger equations studies of QCD. Along the way, we make new predictions for two effective nonphysical couplings: g_{DsDK} = 24.1+2.5/-1.6 and g_{BsBK} = 33.3+4.0/-3.7.

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Bruno El-Bennich, Craig D. Roberts, Mikhail A. Ivanov. 2012-02-02. Heavy-quark symmetries in the light of nonperturbative QCD approaches. https://arxiv.org/abs/1202.0454

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