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arXiv · hep-ph/9712279

Dipenguin-like contributions to D0 - anti-D0 mixing

Alexey A. Petrov
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Abstract

We show that because of the milder GIM suppression, the four-quark dipenguin operator contributes to the short distance piece of the D^0-\bar D^0 mixing amplitude at the same order of magnitude as the box diagram. In addition, we put an upper bound Δm_D^{LDR} \leq 5 \times Δm_D^{box} on a long-distance resonant contribution induced by the penguin mixing.

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Alexey A. Petrov. 1997-12-08. Dipenguin-like contributions to D0 - anti-D0 mixing. https://doi.org/10.1063/1.55989

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