Speaker
Description
The color transparency of a hadron, propagating without absorption in a nucleus, is a fundamental property of QCD, reflecting the hadron's internal structure and the effective size of its color distribution when it is produced at high transverse momentum $Q$. By using the framework of holographic light-front QCD, one can predict the $Q^2$ behavior of the effective transverse size of the hadronic cross section, its dependence on the hadron's twist $\tau$-- the number of constituent quarks of its valence state -- and the quark current which triggers the initial formation of a small color-singlet configuration which can propagate without interaction in a nucleus. One finds a significant delay in $Q^2$ for the onset of color transparency for hadrons with twist $\tau \ge 3$; this can explain the absence of color transparency for the electroproduction of a proton in the kinematic range of existing experimental tests. Remarkably, the onset in $Q^2$ of color transparency for baryons is predicted to strongly differ for electroproduction events corresponding to the spin-conserving (twist-3) Dirac form factor vs. the spin-flip (twist-4) Pauli form factor.
