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arXiv · 0904.3971

$D-\bar D$ mixing in the framework of the HQE revisited

M. Bobrowski·A. Lenz·J. Riedl·J. Rohrwild
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Abstract

We reconsider the leading HQE contributions to the absorptive part of the mixing amplitude of neutral $D$ mesons by taking also $α_s$ corrections and subleading $1/m_c$ corrections into account. We show that these contributions to $Γ_{12}$ do not vanish in the exact SU(3)$_F$ limit and they also can have a large phase. Moreover, we give an example of a new physics model that can enhance these leading HQE terms to $Γ_{12}$, which are orders of magnitude lower than the current experimental expectation, by a factor in the upper double-digit range.

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M. Bobrowski, A. Lenz, J. Riedl, J. Rohrwild. 2009-04-25. $D-\bar D$ mixing in the framework of the HQE revisited. https://arxiv.org/abs/0904.3971

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