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$D^0 - \bar D^0$ Mixing in the Presence of Isosinglet Quarks

G. C. Branco·P. A. Parada·M. N. Rebelo
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Abstract

We analyse $ΔC=2$ transitions in the framework of a minimal extension of the Standard Model where either a $Q=2/3$ or a $Q=-1/3$ isosinglet quark is added to the standard quark spectrum. In the case of a $Q=2/3$ isosinglet quark, it is shown that there is a significant region of parameter space where $D^0 - \bar D^0$ mixing is sufficiently enhanced to be observed at the next round of experiments. On the contrary, in the case of a $Q=-1/3$ isosinglet quark, it is pointed out that obtaining a substancial enhancement of $D^0 - \bar D^0$ mixing, while complying with the experimental constraints on rare kaon decays, requires a contrived choice of parameters.

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G. C. Branco, P. A. Parada, M. N. Rebelo. 1995-01-20. $D^0 - \bar D^0$ Mixing in the Presence of Isosinglet Quarks. https://doi.org/10.1103/physrevd.52.4217

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