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arXiv · 0909.1995

Exclusive decays of χ_{bJ} and η_b into two charmed mesons

Abstract

We develop a framework to study the exclusive two-body decays of bottomonium into two charmed mesons and apply it to study the decays of the C-even bottomonia. Using a sequence of effective field theories, we take advantage of the separation between the scales contributing to the decay processes, 2m_b >> m_c >> Λ_{QCD}. We prove that, at leading order in the EFT power counting, the decay rate factorizes into the convolution of two perturbative matching coefficients and three non-perturbative matrix elements, one for each hadron. We calculate the relations between the decay rate and non-perturbative bottomonium and D-meson matrix elements at leading order, with next-to-leading log resummation. The phenomenological implications of these relations are discussed.

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BibTeXRIS

Regina S. Azevedo, Bingwei Long, Emanuele Mereghetti. 2009-10-06. Exclusive decays of χ_{bJ} and η_b into two charmed mesons. https://doi.org/10.1103/physrevd.80.074026

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