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arXiv · 1701.00969

Is the colour-octet mechanism consistent with the double $J/ψ$ production measurement at B-factories?

Yu Feng·Zhan Sun·Hong-Fei Zhang
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Abstract

Double $J/ψ$ production in $e^+e^-$ collisions involving colour-octet channels are evaluated up to order $α^2α_s^3$. Having implemented the variation of the parameters ($m_c$, $μ_r$ and long-distance matrix elements), we found that the cross sections for producing double $J/ψ$ at B-factories range from $-0.016$fb to $0.245$fb, which are even much smaller than that via the colour-siglet mechanism. Accordingly, this result is consistent with the measurement by the Belle and BABAR Collaborations.

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Yu Feng, Zhan Sun, Hong-Fei Zhang. 2017-01-04. Is the colour-octet mechanism consistent with the double $J/ψ$ production measurement at B-factories?. https://doi.org/10.1140/epjc%2Fs10052-017-4770-4

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