$\eta_{c}\rightarrow l^{+}l^{-}$ and $\chi_{c0}\rightarrow l^{+}l^{-}$ decays revisited

N. Kivel; A. Kupsc

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arXiv · 1602.07460

$\eta_{c}\rightarrow l^{+}l^{-}$ and $\chi_{c0}\rightarrow l^{+}l^{-}$ decays revisited

N. Kivel·A. Kupsc

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Abstract

We present a calculation of $\eta_{c}\rightarrow l^{+}l^{-}$ and $\chi_{c0}\rightarrow l^{+}l^{-}$ decay widths. The amplitudes are computed within leading-order approximation using NRQCD framework. Numerical results for the branchings fractions are presented.

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N. Kivel, A. Kupsc. 2016-02-24. $\eta_{c}\rightarrow l^{+}l^{-}$ and $\chi_{c0}\rightarrow l^{+}l^{-}$ decays revisited. https://arxiv.org/abs/1602.07460

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