Related papers: Phenomenological analysis of two-photon exchange e…
The proton elastic form factor ratio can be measured either via Rosenbluth separation in an unpolarized beam and target experiment, or via the use of polarization degrees of freedom. However, data produced by these two approaches show a…
The apparent discrepancy between the Rosenbluth and the polarization transfer method for the ratio of the electric to magnetic proton form factors can be explained by a two-photon exchange correction which does not destroy the linearity of…
Significant discrepancies have been observed between proton form factors as measured by Rosenbluth separation and polarization transfer techniques. There are indications that this difference may be caused by corrections to the one photon…
The proton elastic form factor ratio is accessible in unpolarized Rosenbluth-type experiments as well as experiments which make use of polarization degrees of freedom. The extracted values show a distinct discrepancy, growing with $Q^2$.…
The effects of two-photon exchange corrections, suggested to explain the difference between measurements of the proton elastic electromagnetic form factors using the polarization transfer and Rosenbluth techniques, have been studied in…
We calculate the effects on the elastic electron-proton scattering cross section of the two-photon exchange contribution with an intermediate $\Delta$ resonance. The $\Delta$ two-photon exchange contribution is found to be smaller in…
Recent polarization transfer measurements of the proton form factors disagree with previous Rosenbluth extractions. In addition to providing insight into the proton structure, the form factors also provide crucial input for the analysis of…
We address the discrepancy between the Rosenbluth and polarization transfer data for the electromagnetic form factors of the nucleon. Assuming that the effect of two-photon corrections on the polarization transfer data is negligible, we…
It has been suggested that two-photon exchange corrections could explain the discrepancy between Rosenbluth extractions of the proton form factors and recent polarization transfer measurements. We propose a precise comparison of…
We use the world's data on elastic electron--proton scattering and calculations of two-photon exchange effects to extract corrected values of the proton's electric and magnetic form factors over the full Q^2 range of the existing data. Our…
Several experiments have extracted proton electromagnetic form factors from elastic cross section measurements using the Rosenbluth technique. Global analyses of these measurements indicate approximate scaling of the electric and magnetic…
Recent polarization transfer measurements of the proton electromagnetic form factors yield very different results from previous Rosenbluth extractions. This inconsistency implies uncertainties in our knowledge of the form factors and raises…
Two-photon exchange contributions to elastic electron-proton scattering cross sections are evaluated in a simple hadronic model including the finite size of the proton. The corrections are found to be small in magnitude, but with a strong…
The comparison of positron-proton and electron-proton elastic scattering cross sections is a sensitive test for the presence of two-photon exchange contributions. Thirty years ago, positron data were considered adequate to set tight limits…
We compute the two photon exchange contributions to elastic scattering of polarized electrons from target protons. We use a nonlocal field theory formalism for this calculation. The formalism maintains gauge invariance and provides a…
World data on the lepton-charge asymmetry in the elastic and inelastic lepton scattering off the proton and nuclei are compiled and discussed. After reviewing the published results, we compare the elastic data to a model calculation of the…
We analyzed the presently available experimental data on nucleon electromagnetic form factors within a multipole model based on dispersion relations. A good fit of the data is achieved by considering the coefficients of the multipole…
We construct a nonlocal gauge invariant Lagrangian to model the electromagnetic interaction of proton. The Lagrangian includes all allowed operators with dimension up to five. We compute the two photon exchange contribution to elastic…
The proton electric and magnetic form factors, $G_E$ and $G_M$, are intrinsically connected to the spatial distribution of charge and magnetization in the proton. For decades, Rosenbluth separation measurements of the angular dependence of…
The proton elastic form factor ratio shows a discrepancy between measurements using the Rosenbluth technique in unpolarized beam and target experiments and measurements using polarization degrees of freedom. The proposed explanation of this…