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arXiv · 1803.11135

Charged-to-neutral meson yield ratio at $\psi(3770)$ and $\Upsilon(4S)$ revisited

M. B. Voloshin
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Abstract

The recent precision measurement of the relative yield of $D^+D^-$ and $D^0 \bar D^0$ meson pairs at the $\psi(3770)$ peak in $e^+e^-$ annihilation is about 3.7 sigma away from a straightforward theoretical estimate. It is argued that combined with an even more significant deviation of similar ratio for the $B$ mesons at the $\Upsilon(4S)$ peak, this provides an insight into the structure of heavy mesons and requires both a form factor, corresponding to their finite `size', and a strong interaction between the mesons mesons in the isovector state $I^G(J^P) = 1^+(1^-)$. It is also argued that the data for the $D$ and $B$ mesons are possibly compatible with the heavy quark limit of the same meson-antimeson strong interaction in both systems.

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M. B. Voloshin. 2018-03-29. Charged-to-neutral meson yield ratio at $\psi(3770)$ and $\Upsilon(4S)$ revisited. https://doi.org/10.1103/physrevd.97.114023

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