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Anomalous enhancement of a penguin hadronic matrix element in B->K eta'

J. -M. Gerard·E. Kou
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Abstract

We estimate the density matrix element for the pi^0, eta and eta' production from the vacuum in the large-N_c limit. As a consequence, we find that the QCD axial anomaly leads to highly non-trivial corrections to the usual flavour SU(3) relations between B^0-> K^0 pi^0, B^0-> K^0 eta and B^0-> K^0 eta' decay amplitudes. These corrections may explain why the B-> K eta' branching ratio is about six times larger than the B-> K pi one.

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J. -M. Gerard, E. Kou. 2006-09-28. Anomalous enhancement of a penguin hadronic matrix element in B->K eta'. https://doi.org/10.1103/physrevlett.97.261804

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