Speaker
Description
We will present recent results from the COMPASS collaboration on hard exclusive muoproduction of mesons using 160 GeV polarized beams scattering off a liquid hydrogen target. The data cover a unique kinematic regime in the intermediate Bjorken-$x$ domain and moderate $Q^2$, providing new constraints on the nucleon’s generalized parton structure. The measurements include cross-section of exclusive $\pi_0$ production, which is particularly sensitive to chiral-odd Generalised Parton Distributions (GPDs), and Spin Density Matrix Elements (SDMEs) of light vector mesons, which indicate a violation of $s$-channel helicity conservation. These observables offer critical input for global GPD fits and open the possibility to access transversity GPDs through a model-dependent interpretation of exclusive vector meson production amplitudes.
