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Measurement of Azimuthal Asymmetries in Inclusive Production of Hadron Pairs in e+e- Annihilation at sqrt{s} = 10.58 GeV

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 نشر من قبل Ralf Seidl
 تاريخ النشر 2008
  مجال البحث
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The Collins effect connects transverse quark spin with a measurable azimuthal asymmetry in the yield of hadronic fragments around the quarks momentum vector. Using two different reconstruction methods we measure statistically significant azimuthal asymmetries for charged pion pairs in e+e- annihilation at center-of-mass energies of 10.52 GeV and 10.58 GeV, which can be attributed to the fragmentation of primordial quarks with transverse spin components. The measurement was performed using a dataset of 547 fb^{-1} collected by the Belle detector at KEKB improving the statistics of the previously published results by nearly a factor of 20.



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