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arXiv · 0803.1118

First Observation of the Decay D_s^+ to proton anti-neutron

CLEO Collaboration·S. B. Athar
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Abstract

Using e^+e^- -> D_s^*+ D_s^- data collected near the peak D_s production energy, E_cm=4170 MeV, with the CLEO-c detector, we present the first observation of the decay D_s^+ -> proton anti-neutron. We measure a branching fraction B(D_s^+ -> p anti-n = (1.30 +- 0.36 +0.12 -0.16) x 10^-3. This is the first observation of a charmed meson decaying into a baryon-antibaryon final state.

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CLEO Collaboration, S. B. Athar. 2008-04-25. First Observation of the Decay D_s^+ to proton anti-neutron. https://doi.org/10.1103/physrevlett.100.181802

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