Forward Tagging at the EIC: From Nucleon Spin to Meson structure

Understanding the origin of the spin and mass of the nucleon—in particular, how they emerge from partons dynamics — is an overarching challenge for nuclear physics research. In this talk I will present recent progress in the development of an experimental program to address these questions at the forthcoming Electron Ion Collider. First, I will discuss double tagging of spectator protons emitted in the deep inelastic scattering (DIS) of electrons off neutrons in polarized ³​He nuclei. These novel processes can only be accessed at the EIC and will lead to a x5 – x10 improvements in the uncertainty of the neutron asymmetry measurement which is crucial for a flavor decomposition of the nucleon spin structure. Next, I will discuss high-impact measurements of pion and kaon structure functions over a wide range of Q², which provide fundamental insight to the generation of hadronic mass. Both of these measurements, and several others, are made possible by the unique capabilities of the far-forward detection region of the EIC