First extraction of transversity from electron-proton and proton-proton data

We present the first extraction of the transversity distribution based on the global analysis of pion-pair production in deep-inelastic scattering and in proton-proton collisions with one transversely polarized proton. The extraction relies on the knowledge of di-hadron fragmentation functions, which are taken from the analysis of electron-positron annihilation data. For the first time, the chiral-odd transversity is extracted from a global analysis similar to what is usually done for the chiral-even spin-averaged and helicity distributions. The knowledge of transversity is important among other things for detecting possible signals of new physics in high-precision low-energy experiments.