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arXiv · hep-ex/0004034

A measurement of lifetime differences in the neutral D-meson system

The FOCUS Collaboration
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Abstract

Using a high statistics sample of photoproduced charm particles from the FOCUS experiment at Fermilab, we compare the lifetimes of neutral D mesons decaying via D0 to K- pi+ and K- K+ to measure the lifetime differences between CP even and CP odd final states. These measurements bear on the phenomenology of D0 - D0bar mixing. If the D0 to K-pi+ is an equal mixture of CP even and CP odd eigenstates, we measure yCP = 0.0342 \pm 0.0139 \pm 0.0074.

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The FOCUS Collaboration. 2000-06-05. A measurement of lifetime differences in the neutral D-meson system. https://doi.org/10.1016/s0370-2693(00)00694-8

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