Hard Exclusive Pseudo-scaler Meson Productions with CLAS12 and Beyond

Hard exclusive meson production is a powerful tool to access generalized parton distributions (GPDs) that open up the possibility to explore the 3D structure of hadrons at parton level, and their potential to unravel the spin structure of the nucleon. New data were recently collected with the CLAS12 spectrometer in Hall B at Jefferson Lab with longitudinally polarized 10.6 GeV electrons scattered off an unpolarized liquid hydrogen target. In this talk, we present new experimental measurements of beam spin asymmetry for the hard exclusive pseudo-scaler meson productions in a wide kinematic region. We also discuss exciting scientific opportunities for a possible 22 GeV energy upgrade to CEBAF with CLAS12 High-Luminosity Upgrade.