Double deeply virtual Compton scattering with positron beams at SoLID

Double Deeply Virtual Compton Scattering (DDVCS) is the only experimental channel for determination of dependence Generalized Parton Distributions (GPDs) on both average and transferred momentum independently. The physics observables electron induced di-muon production reaction $$\overrightarrow{e}^{\pm }p \rightarrow e^{\pm }p\mu ^+\mu ^-$$ off unpolarized hydrogen are discussed. Their measurement with high luminosity large acceptance SoLID spectrometer at Thomas Jefferson National Accelerator Facility, using polarized positron beams 11 GeV investigated. This configuration shown to provide unprecedented access GPDs real imaginary parts Form Factor $${\mathcal H}$$ in an unexplored phase space, enable exploratory investigation higher twist effects.