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Probing for the Charm Content of $B$ and $Υ$ Mesons

Chia-Hung V. Chang·Wei-Shu Hou
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Abstract

A slow $J/ψ$ bump exists in the inclusive $B\to J/ψ+ X$ spectrum, while the softness of $J/ψ$ spectrum in $Υ(1S) \to J/ψ+ X$ decay is in strong contrast with expectations from color octet mechanism. We propose {\it intrinsic} charm as the explanation:the former is due to $\bar B\to J/ψD π$,with three charm quarks in the final state; the latter is just a small fraction of $Υ(1S) \to (c\bar c)_{\rm slow} + 2$"jet" events, where the slow moving $c\bar c$ system evolves into $D^{(*)}$ pairs. Experimental search for these phenomena at B Factories and the Tevatron is strongly urged, as the implications go beyond QCD.

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Chia-Hung V. Chang, Wei-Shu Hou. 2001-05-24. Probing for the Charm Content of $B$ and $Υ$ Mesons. https://doi.org/10.1103/physrevd.64.071501

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