Hard exclusive π^-Δ⁺⁺ production off the proton with CLAS12 at JLAB

Hard exclusive pion production is a well established tool to study Generalized Parton

Distributions (GPDs). During the last decade, extensive studies have been performed on hard

exclusive π⁰ and π⁺ production off the proton. However, hard exclusive π^- production off the

proton is so far nearly unexplored. It can be described based on N→Δ⁺⁺ transition GPDs

which can help us to gain insights into the 3D structure of the p to Δ transition. The talk will

present a study of the polarized cross section ratio σ_LT’/σ₀ from hard exclusive π electroproduction

off an un-polarized hydrogen target in the forward kinematic regime (-t/Q² << 1)

based on beam-spin asymmetry measurements with CLAS12 at JLAB. The results will be

compared to previous studies on hard exclusive π⁰ and π⁺ production, which show an opposite

sign of the cross section ratio, and discussed in the context of a GPD and transition GPD

based description.