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arXiv · 0808.2985

$Υ$ decay to two-charm quark jets as a Probe of the Color Octet Mechanism

Yu-Jie Zhang·Kuang-Ta Chao
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Abstract

We calculate the decay rate of bottomonium to two-charm quark jets $Υ\to c \bar c$ at the tree level and one-loop level including color-singlet and color-octet $b \bar b$ annihilations. We find that the short distance coefficient of the color-octet piece is much larger than the color-singlet piece, and that the QCD correction will change the endpoint behavior of the charm quark jet. The color-singlet piece is strongly affected by the one-loop QCD correction. In contrast, the QCD correction to the color-octet piece is weak. Once the experiment can measure the branching ratio and energy distribution of the two-charm quark jets in the $Υ$ decay, the result can be used to test the color octet mechanism or give a strong constraint on the color-octet matrix elements.

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Yu-Jie Zhang, Kuang-Ta Chao. 2008-11-04. $Υ$ decay to two-charm quark jets as a Probe of the Color Octet Mechanism. https://doi.org/10.1103/physrevd.78.094017

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