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We discuss two applications of the {\it Virtuality Distribution Amplitudes}(VDA) formalism developed in our recent papers. We start with an overview ofthe main properties of the pion distribution amplitude emphasizing thequantitative measures of its width, and possibility to access them through thepion transition form factor studies. We formulate the basic concepts of the VDAapproach and introduce the pion transverse momentum distribution amplitude(TMDA) which plays, in a covariant Lagrangian formulation, a role similar tothat of the pion wave function in the 3-dimensional Hamiltonian light-frontapproach. We propose simple factorized models for soft TMDAs, and use them todescribe existing data on the pion transition form factor, thus fixing thescale determining the size of the transverse-momentum effects. Finally, weapply the VDA approach to the one-gluon exchange contribution for the pionelectromagnetic form factor. We observe a very late $Q^2 \gtrsim 20$ GeV$^2$onset of transition to the asymptotic pQCD predictions and show that in the$Q^2 \lesssim 10$ GeV$^2$ region there is essentially no sensitivity to theshape of the pion distribution amplitude. Furthermore, the magnitude of theone-gluon exchange contribution in this region is estimated to be an order ofmagnitude below the Jefferson Lab data, thus leaving the Feynman mechanism asthe only one relevant to the pion electromagnetic form factor behavior foraccessible $Q^2$.

Pion Electromagnetic Form Factor in Virtuality Distribution Formalism