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

TL;DR

This paper presents the first extraction of the u and d-flavor transversity parton distribution functions using dihadron fragmentation functions from e+e- and SIDIS data, advancing understanding of nucleon spin structure.

Contribution

It introduces a novel method combining e+e- annihilation and SIDIS data to extract transversity PDFs via dihadron fragmentation functions.

Findings

First extraction of u and d transversity PDFs.

Identification of a nonzero asymmetry related to quark transverse polarization.

Demonstration of the effectiveness of dihadron fragmentation functions in spin studies.

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 $\pi^+\pi^-$ 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 $ep^{\uparrow}\to e'(\pi^+\pi^-)X$ has led to the first extraction of the u and d-flavor transversity parton distribution function in the framework of collinear factorization.