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arXiv · hep-ph/0304114

Direct J/psi and psi' hadroproduction via fragmentation in the collinear parton model and k_T-factorization approach

V. A. Saleev·D. V. Vasin
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Abstract

The p_T-spectra for direct J/psi and psi' in hadroproduction at Tevatron energy have been calculated based on NRQCD formalism and fragmentation approximation in the collinear parton model and k_T-factorization approach. We have described the CDF data and obtained a good agreement between the predictions obtained in the parton model and k_T-factorization approach. We performed the calculations using the relevant leading order in alpha_s hard amplitudes and the equal values of the color-octet long-distance matrix elements for the both models.

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V. A. Saleev, D. V. Vasin. 2003-10-27. Direct J/psi and psi' hadroproduction via fragmentation in the collinear parton model and k_T-factorization approach. https://doi.org/10.1103/physrevd.68.114013

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