Yi-Jie Li, Guang-Zhi Xu, Kui-Yong Liu, Yu-Jie Zhang
The relativistic corrections to the productions of double J/psi, double Upsilon, and J/psi+Upsilon at the Tevatron and the LHC were investigated within the frame of nonrelativistic QCD. The ratios of short distance coefficients between relativistic correction and leading order result for color singlet and color octet states in large p_T limit are approximately -1,-11/3, respectively, for pair production. And for J/psi+Upsilon process the ratio is -11/6 for the CO channel. The K factors of relativistic corrections for color singlet and color octet double J/psi production are -0.23 and -0.84 with adopting v^2=0.23. The relativistic corrections significantly dilute the difference between the shape of color-singlet differential cross sections and the color-octet's at leading order. Also our results show that the single parton scattering model may be enough to explain the LHCb data for the J/psi pair production.
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http://arxiv.org/abs/1303.1383
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