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J/psi production at the Tevatron and HERA: the effect of k_T smearing

K. Sridhar·A. D. Martin·W. J. Stirling
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Abstract

We study the effects of intrinsic transverse momentum smearing on J/psi production both at the Tevatron and at HERA. For the case of large-p_T J/psi production at the Tevatron, the effects due to k_T smearing are mild. On the other hand, inelastic J/psi photoproduction at HERA is very sensitive to the k_T smearing and, in fact, with a reasonable value of it is possible to resolve the large-z discrepancy seen by comparing non-relativistic QCD (NRQCD) predictions with the HERA data. We conclude that, with the present kinematic cuts, photoproduction at HERA is not a good test of NRQCD.

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K. Sridhar, A. D. Martin, W. J. Stirling. 1998-06-04. J/psi production at the Tevatron and HERA: the effect of k_T smearing. https://doi.org/10.1016/s0370-2693(98)00956-3

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