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arXiv · hep-ph/9511314

A Strong QCD Enhancement of CP Violation in Charmed Meson Decays?

Frank E. Close·Harry J. Lipkin
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Abstract

The mass difference of $c$ and $u$ quarks is similar to the energy needed to excite gluonic degrees of freedom in strong QCD. This underpins the degeneracy of $D$ and a recently observed candidate hybrid excitation of the $π$ at$\sim 1.8$GeV and may generate a strong analogue of Penguin mixing together with a measurable CP-violation in $D$ and $D_s$ decays.

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Frank E. Close, Harry J. Lipkin. 1995-11-14. A Strong QCD Enhancement of CP Violation in Charmed Meson Decays?. https://doi.org/10.1016/0370-2693(96)00042-1

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