Speaker
Description
Pion and kaons, the lightest bound states in the hadron spectrum, are essential to understand the strong interaction in the non-perturbative domain of QCD. They are connected to the Goldstone modes of dynamical chiral symmetry breaking, the mechanism thought to generate nearly all hadron mass in the visible universe. Pion and kaons thus provide a novel perspective on the emergent hadron mass and confinement mechanisms in QCD. The distribution of the fundamental constituents, the quarks and gluons, is expected to be different in pions, kaons, and nucleons. However, experimental data are sparse. As a result, there has been persistent doubt about the behavior of the pion's valence quark structure function at large Bjorken-x and virtually nothing is known about the contribution of gluons. Experiments at 12 GeV JLab using the Sullivan process may provide insight. The Electron-Ion Collider with an acceptance optimized for forward physics could vastly extend the kinematic range of pion and kaon charts. This would allow for measurements testing if the origin of mass is encoded in the differences of gluons in pions, kaons, and nucleons, and measurements that could serve as a test of assumptions used in the extraction of structure functions and the pion and kaon form factors. Measurements at an EIC would also allow to explore the effect of gluons at high x. In this talk we will discuss new results from JLab and the prospects of such measurements at EIC.