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arXiv · 1508.07686

Three symmetry breakings in strong and radiative decays of strange heavy mesons

Chi-Yee Cheung·Chien-Wen Hwang
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Abstract

In this paper, we investigate three symmetry breaking effects in strong and radiative decays of strange heavy mesons. We study 1/m_Q corrections within the heavy quark effect theory, as well as SU(3) and SU(2) symmetry breakings induced by light quark mass differences and the η-πmixing vertex. These effects are studied in a covariant model. The numerical results show that the 1/m_Q corrections of the coupling constants are consistent with α_s Λ_{QCD}/m_Q. The SU(3) symmetry violating effect of the strong coupling constant is obviously larger than that of the magnetic coupling constant. The value of the η-πmixing vertex has some changes because of the renewed data. As compared with the other theoretical calculations and the experimental data, our radiative decay rates are much larger than those of the other theoretical methods, except for \chiPT; however, our branching ratios are close to the experimental data.

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Chi-Yee Cheung, Chien-Wen Hwang. 2016-01-15. Three symmetry breakings in strong and radiative decays of strange heavy mesons. https://doi.org/10.1140/epjc%2Fs10052-016-3883-5

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