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arXiv · 1008.5077

Updated Search for the Flavor-Changing Neutral-Current Decay D^0 \to μ + μ-

The CDF Collaboration·T. Aaltonen
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Abstract

We report on a search for the flavor-changing neutral-current decay D0 \to μ+ μ- in pp collisions at \surd s = 1.96 TeV using 360 pb-1 of integrated luminosity collected by the CDF II detector at the Fermilab Tevatron collider. A displaced vertex trigger selects long-lived D0 candidates in the μ+ μ-, π+π-, and K-π+ decay modes. We use the Cabibbo-favored D0 \to K-π+ channel to optimize the selection criteria in an unbiased manner, and the kinematically similar D0 \toπ+ π- channel for normalization. We set an upper limit on the branching fraction (D0 --> μ+ μ-) < 2.1 E-7 (3.0 E-7) at the 90% (95%) confidence level.

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The CDF Collaboration, T. Aaltonen. 2010-08-30. Updated Search for the Flavor-Changing Neutral-Current Decay D^0 \to μ + μ-. https://doi.org/10.1103/physrevd.82.091105

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