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Measurement of Azimuthal Asymmetries in Inclusive Production of Hadron Pairs in e+e- Annihilation at Belle

The Belle Collaboration·R. Seidl
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Abstract

The Collins effect connects transverse quark spin with a measurable azimuthal dependence in the yield of hadronic fragments around the quark's momentum vector. Using two different reconstruction methods we observe statistically significant azimuthal asymmetries for charged pion pairs in e+e- annihilation at a center-of-mass energy of 10.52 GeV, which can be attributed to a transverse polarization of the primordial quarks. The measurement was performed using a sample of 79 million hadronic events collected with the Belle detector.

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The Belle Collaboration, R. Seidl. 2006-07-11. Measurement of Azimuthal Asymmetries in Inclusive Production of Hadron Pairs in e+e- Annihilation at Belle. https://doi.org/10.1103/physrevlett.96.232002

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