U2 - 5017 (Universita Milano Bicocca)
Speakers: Ignacio Borsa
The study of the internal spin structure of the proton in terms of the contributions from quarks, anti-quarks and gluons is a key focus of modern particle physics. These contributions can be described in terms of the longitudinally polarized parton distribution functions (pPDFs) or helicity PDFs, which are probed in high-energy scattering processes involving polarized nucleons. In this seminar I will present the results of our recent next-to-next-to-leading order (NNLO) fully-global QCD analysis of the proton's helicity PDFs, as well as some recent theory developments for precision calculations for polarized processes. Before commenting on the method and obtained results, I will make a short introduction about longitudinally-polarized collisions and the spin content of the proton.