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arXiv · 1206.1836

Status on the transversity parton distribution: the dihadron fragmentation functions way

A. Courtoy·Alessandro Bacchetta·Marco Radici
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Abstract

We report on the extraction of dihadron fragmentation functions (DiFF) from the semiinclusive production of two hadron pairs in back-to-back jets in e+e- annihilation. A nonzero asymmetry in the correlation of azimuthal orientations of opposite $π^+π^-$ pairs is related to the transverse polarization of fragmenting quarks through a significant polarized DiFF. A combined analysis of this asymmetry and the spin asymmetry in the SIDIS process $ep^{\uparrow}\to e'(π^+π^-)X$ has led to the first extraction of the u and d-flavor transversity parton distribution function in the framework of collinear factorization.

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A. Courtoy, Alessandro Bacchetta, Marco Radici. 2012-06-08. Status on the transversity parton distribution: the dihadron fragmentation functions way. https://arxiv.org/abs/1206.1836

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