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arXiv · hep-ph/0209135

Polarized J/psi production from B mesons at the Tevatron

Abstract

In the framework of NRQCD and parton model, we estimate in detail,the production cross section for polarized J/psi from B meson decays. In order to contrast with data, we also take into account additional J/psi production due to decay of excited charmonium states. We calculate the helicity parameter, alpha, and as an application, we study our results for the Tevatron. This is in contrast to the earlier studies which were performed for prompt J/psi production from p pbar collisions. Our estimates are, for J/psi from B decays, alpha_{J/psi} = -0.04 +- 0.06 and for B decays to psi', alpha_{psi'}= -0.03 +- 0.07. These results have been evaluated in the J/psi transverse momentum interval, 10 GeV < k_T < 30 GeV. In the limit of the color singlet model, alpha shows a direct dependence on the Peterson parameter, thereby reflecting the dynamics of the b quark hadronization. With Run II of the Tevatron, it is expected that the fits for alpha will improve by about a factor of 50, leading to better limits on the matrix elements.

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BibTeXRIS

V. Krey, K. R. S. Balaji. 2002-12-11. Polarized J/psi production from B mesons at the Tevatron. https://doi.org/10.1103/physrevd.67.054011

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