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A novel method is employed to compute the pion electromagnetic form factor, F_pi(Q^2), on the entire domain of spacelike momentum transfer using the Dyson-Schwinger equation (DSE) framework in quantum chromodynamics (QCD). The DSE architecture unifies this prediction with that of the pions valence-quark parton distribution amplitude (PDA). Using this PDA, the leading-order, leading-twist perturbative QCD result for Q^2 F_pi(Q^2) underestimates the full computation by just 15% on Q^2>~8GeV^2, in stark contrast with the result obtained using the asymptotic PDA. The analysis shows that hard contributions to the pion form factor dominate for Q^2>~8GeV^2 but, even so, the magnitude of Q^2 F_pi(Q^2) reflects the scale of dynamical chiral symmetry breaking, a pivotal emergent phenomenon in the Standard Model.
A Poincare-covariant quark+diquark Faddeev equation is used to compute nucleon elastic form factors on $0leq Q^2leq 18 ,m_N^2$ ($m_N$ is the nucleon mass) and elucidate their role as probes of emergent hadronic mass in the Standard Model. The calcula
The electromagnetic form factor of the pion in the space-like region, and at finite temperature, $F_{pi}(Q^{2},T)$, is obtained from a QCD Finite Energy Sum Rule. The form factor decreases with increasing T, and vanishes at some critical temperature,
A dressed-quark core contribution to nucleon electromagnetic form factors is calculated. It is defined by the solution of a Poincare covariant Faddeev equation in which dressed-quarks provide the elementary degree of freedom and correlations between
The pion electromagnetic form factor is calculated at lower and higher momentum transfer in order to explore constituent quark models and the differences among those models. In particular, the light-front constituent quark model is utilized here to c
We compute nucleon and Roper e.m. elastic and transition form factors using a symmetry-preserving treatment of a contact-interaction. Obtained thereby, the e.m. interactions of baryons are typically described by hard form factors. In contrasting this