Dynamical Higher-Twist and High x-Bjorken Phenomena: A Window to Quark-Quark Correlations in QCD

Measurements of the power-law corrections to Bjorken scaling and the behavior of structure functions in the highly stressed xbj --> 1 regime of electroproduction can lead to new information on the quark-quark correlations controlling the nucleon wavefunction at far-off-shell kinematics. Electroproduction on nuclei at A > xbj > 1 are sensitive to hidden-color components of the nuclear wavefunction. A distinctive dynamical higher-twist order of (1/Q2) correction, which is dynamically enhanced at high xbj, can arise from the interference of amplitudes where the lepton scatters from two different valence quarks of the target. Measurements of the parity-violating left-right asymmetry ALR in elastic and inelastic polarized electron scattering at large xbj can confirm the structure of the quark-quark correlations and other QCD physics at the amplitude level