  Using the relativistic Eikonal approximation, we study the one and two photon
exchange amplitudes in elastic electron-nucleon scattering for the case of
transversely polarized nucleons with unpolarized electrons beam. In our
approach, we utilize the convolution theory of Fourier transforms and the
transverse charge density in transverse momentum space to evaluate the one and
two photon exchange Eikonal amplitudes. The results obtained for the $2\gamma$
amplitude in impact parameter space are compared to the corresponding 4D case.
We show that while the one and two photon cross sections are azimuthally
symmetric, the interference term between them is azimuthally asymmetric, which
is an indication of an azimuthal single spin asymmetry for proton and neutron
which can be attributed to the fact that the nucleon charge density is
transversely (azimuthally) distorted in the transverse plane for transversely
polarized nucleons. In addition, the calculations of the interference term for
proton and neutron show agreement in sign and magnitude of the existence data
and calculations for transverse target single spin asymmetry.
