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Search for the Flavor-Changing Neutral Current Decay $D^0 \to μ^+μ^-$ with the HERA-B Detector

B Collaboration·I. Abt
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Abstract

We report on a search for the flavor-changing neutral current decay $D^0 \to μ^+μ^-$ using $50 \times 10^6$ events recorded with a dimuon trigger in interactions of 920 GeV protons with nuclei by the HERA-B experiment. We find no evidence for such decays and set a 90% confidence level upper limit on the branching fraction $Br(D^0 \to μ^+μ^-) <2.0 \times 10^{-6}$.

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B Collaboration, I. Abt. 2004-05-19. Search for the Flavor-Changing Neutral Current Decay $D^0 \to μ^+μ^-$ with the HERA-B Detector. https://doi.org/10.1016/j.physletb.2004.06.097

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