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arXiv · hep-ph/0312003

Spin Alignment of Vector Mesons in Polarized and Unpolarized High Energy Reactions

Zuo-tang Liang
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Abstract

Recent e+e- annihilation experiments show a striking spin alignment of vector mesons produced in the fragmentation of a polarized quark.We show that these data imply a simple relation between the polarization of the anti-quark, which is produced in the fragmentation process to combine with the fragmenting quark to form the meson, and that of the fragmenting quark. After having obtained a good fit to the e+e- data, we extend the calculations to lepton-nucleon and nucleon-nucleon collisions with polarized beams. We also discuss the relation between the spin alignment of vector meson in unpolarized hadron-hadron collisions and the single-spin left-right asymmetry. We make predictions for the polarization of the vector mesons in these reactions which can be checked by future experiments.

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Zuo-tang Liang. 2003-11-29. Spin Alignment of Vector Mesons in Polarized and Unpolarized High Energy Reactions. https://arxiv.org/abs/hep-ph/0312003

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