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Unifying aspects of polarization of vector mesons from hard production in DIS and at Tevatron

N. N. Nikolaev
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Abstract

Virtual photons have both the transverse and longitudinal polarization. In the inclusive DIS the impact of longitudinal photons, quantified by R=sigmaL/\igmaT sim 0.2, is marginal, but in diffractive DIS with excitation of small mass hadronic states or exclusive diffraction into vector mesons, QCD predicts R >> 1 in agreement with the experiment. After a brief review of the modern status of QCD theory of diffractive vector meson production I argue that longitudinally polarized gluons give rise to a large longitudinal polarization of the prompt JPsi and Psiprim observed at the Tevatron.

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N. N. Nikolaev. 2001-08-08. Unifying aspects of polarization of vector mesons from hard production in DIS and at Tevatron. https://doi.org/10.1016/s0375-9474(01)01495-6

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