The European Muon Collaboration effect in light-front Hamiltonian dynamics

A new and rigorous light-front formalism for electron deep inelastic scattering on unpolarized nuclei, in Bjorken limit, is proposed. It preserves Poincaré covariance, macroscopic locality, both number of particles and momentum sum rules. The approach is applied to the A=3 iso-doublet, very relevant for the flavor decomposition of the parton distribution functions and in view of the planned operation with unpolarized and polarized beams at the Electron-Ion Collider. At variance with previous light-front estimates, our procedure, including a realistic nuclear description and free-nucleon structure functions, predicts a sizable European Muon Collaboration effect for 3He. This will allow to analyze deviations from the proposed baseline in terms of genuine QCD effects. The extension to heavier nuclei is straightforward, although numerically challenging.