Quasi-elastic knockout of pions and kaons from nucleons by high-energy electrons and quark microscopy of “soft” meson degrees of freedom in the nucleon

Abstract

Electro-production of pions and kaons at the kinematics of quasi-elastic knockout (which is well known in the physics of atomic nucleus and corresponds to the t-pole diagram) is proposed for obtaining their momentum distribution (MD) in various channels of virtual decay N→ B+ π, B= N, Δ, N ∗ , N ∗∗ , and N→ Y+ K, Y= Λ, Σ. It is a powerful tool for investigation of a quark microscopic picture of the meson cloud in the nucleon. A model of scalar q q ̄ ( 3P 0 ) fluctuation in the non-trivial QCD vacuum is used to calculate pion and kaon momentum distributions (MD) in these channels.