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arXiv · 1201.4678

Study of Collins Asymmetries at BaBar

I. Garzia
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Abstract

Transversity distribution describes the quark transverse polarization inside a transversely polarized nucleon. It is the less known leading-twist piece of the QCD description of the partonic structure of the nucleon. Transversity can be extracted from semi-inclusive deep inelastic scattering (SIDIS) where, however, it couples to a new, unknown fragmentation function, called Collins function. We present the preliminary results of the measurement of the azimuthal asymmetries in the process e^+e^- -> qqbar -> pi pi X, where the two pions are produced in opposite hemispheres. These preliminary results are based on a data sample of about 45 fb^{-1}, collected by the BABAR experiment at a center-of-mass energy of 10.54 GeV, and are compared with the Belle measurements.

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I. Garzia. 2012-01-23. Study of Collins Asymmetries at BaBar. https://doi.org/10.1393/ncc%2Fi2012-11210-1

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