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arXiv · hep-ph/9911436

Polarization of Prompt J/psi at the Tevatron

Eric Braaten·Bernd A. Kniehl·Jungil Lee
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Abstract

The polarization of prompt J/psi at the Fermilab Tevatron is calculated within the nonrelativistic QCD factorization framework. The contribution from radiative decays of P-wave charmonium states decreases, but does not eliminate, the transverse polarization at large transverse momentum. The angular distribution parameter alpha for leptonic decays of the J/ψis predicted to increase from near 0 at p_T = 5 GeV to about 0.5 at p_T = 20 GeV. The prediction is consistent with measurements by the CDF Collaboration at intermediate values of p_T, but disagrees by about 3 standard deviations at the largest values of p_T measured.

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Eric Braaten, Bernd A. Kniehl, Jungil Lee. 2000-07-26. Polarization of Prompt J/psi at the Tevatron. https://doi.org/10.1103/physrevd.62.094005

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