Toward Precision Helicity PDFs from Global DIS and SIDIS Fits with Projected EIC Measurements

• Hamzeh Khanpour (Department of Physics, AGH University of Kraków, Poland)

The Hadron and Partonic Structure (HAPS) Collaboration is an international effort devoted to precision studies of hadron structure within perturbative QCD. In this talk, we will first present an overview of our HAPS Collaboration, its members and institutional network, recent publications, and ongoing projects. We will then focus on our recent determination of polarized proton PDFs, HAPS-pPDF1.0, based on a global NLO analysis of longitudinally polarized inclusive DIS and charge-separated SIDIS data. Particular attention will be given to the projected impact of future Electron-Ion Collider SIDIS measurements for identified pion and kaon production. We will discuss the fit methodology, stability studies, comparisons with recent polarized-PDF determinations, and the resulting improvement in the quark and gluon helicity contributions to the proton spin. Finally, we will outline ongoing HAPS activities and future directions, including diffractive PDFs and EIC-related global QCD analyses.