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A Crucial Test for Color-Octet Production Mechanism in Z^0 Decays

Cong-feng Qiao·Feng Yuan·Kuang-Ta Chao
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Abstract

The direct production rates of $D$-wave charmonia in the decays of $Z^0$ is evaluated. The color-octet production processes $Z^0\rightarrow ^3D_J(c\bar c) q\bar q$ are shown to have distinctively large branching ratios, the same order of magnitude as that of $J/ψ$ prodution, as compared with other $D$-wave charmonium production mechanisms. This may suggest a crucial channel to test the color-octet mechanism as well as to observe the $D$-wave charmonium states in $Z^0$ decays. In addition, a signal for the $^3D_J$ charmonium as strong as $J/ψ$ or $ψ^\prime$ with large transverse momentum at the Tevatron should also be observed.

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Cong-feng Qiao, Feng Yuan, Kuang-Ta Chao. 1996-09-08. A Crucial Test for Color-Octet Production Mechanism in Z^0 Decays. https://doi.org/10.1103/physrevd.55.4001

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