Speaker
Description
Spin-dependent azimuthal asymmetries provide a powerful probe of hadron transverse structure and TMD dynamics. In this talk, I will present a phenomenological study of Collins asymmetries in pion-in-jet production in polarized proton-proton collisions within a TMD framework with a collinear initial-state configuration. Using transversity distributions and Collins fragmentation functions extracted from SIDIS and electron-positron annihilation data, we obtain a consistent description of STAR measurements, supporting both the universality of the Collins function and the validity of TMD factorization.
I will also present predictions for lepton-proton collisions at the future Electron-Ion Collider, including quasi-real photon contributions. These measurements will provide further tests of Collins-function universality and enable its flavor separation through the controlled partonic initial state. This is expected to significantly improve constraints on transversity, extending sensitivity to poorly known kinematic regions and providing access to its sea-quark component.