The complete experiment for $e^{\mp }N$ elastic scattering in presence of two-photon exchange

Abstract

We propose possible methods to measure the nucleon electromagnetic form factors in presence of two-photon exchange. Using a general parametrization of the spin structure of the matrix element for elastic $eN$-scattering, in terms of three independent complex amplitudes, we show that the measurements of the differential cross section for electron and positron nucleon elastic scattering, in the same kinematical conditions, allows to extract the nucleon electromagnetic form factors. The same is correct for the polarization method, with the measurement of the $P_{x,z}$ components of the final nucleon polarization (for the scattering of longitudinally polarized electrons and positrons). An alternative way, in absence of positron beam, is to measure a definite set of T-odd polarization observables, which includes three different experiments or only T-even observables, with five independent experiments. In both cases, the ratio $G_E(Q^2)/G_M(Q^2)$ is related to quantities of the order of $\alpha$, which requires different polarization experiments of very high accuracy.

arXiv comment11 pages v2: additional formulas, small corrections

References in corpus (10)

• The ratio of proton's electric to magnetic form factors measured by polarization transfer
• Measurement of GEp/GMp in ep -> ep to Q2 = 5.6 GeV2
• Two-photon exchange and elastic electron-proton scattering
• How to reconcile the Rosenbluth and the polarization transfer method in the measurement of the proton form factors
• Electroproduction of the Delta Resonance at High Momentum Transfer
• Radiative Corrections to Electron-Proton Scattering
• Large Momentum Transfer Measurements of the Deuteron Elastic Structure Function A(Q^2) at Jefferson Laboratory
• A precise measurement of the deuteron elastic structure function A(Q^2)
• Model independent radiative corrections in processes of polarized electron-nucleon elastic scattering
• QED Radiative Corrections to Asymmetries of Elastic ep-scattering in Hadronic Variables

Cited by in corpus (23)

• Measurement of the Transverse Beam Spin Asymmetry in Elastic Electron Proton Scattering and the Inelastic Contribution to the Imaginary Part of the Two-Photon Exchange Amplitude
• Model independent properties of two-photon exchange in elastic electron proton scattering
• Search for evidence of two photon contribution in elastic electron proton data
• General analysis of polarization phenomena in $e^{+}+e^{-}\to N+\bar{N}$ for axial parametrization of two--photon exchange
• Polarization phenomena in elastic $e^{\mp }N$ scattering, for axial parametrization of two-photon exchange
• Feasibility studies of the time-like proton electromagnetic form factor measurements with PANDA at FAIR
• Comparison of Neural Network and Hadronic Model Predictions of Two-Photon Exchange Effect
• Polarization effects in the reaction $\bar{p}+p\to e^{+}+e^{-}$ in presence of two-photon exchange
• Two-Photon Exchange Contribution to Proton Form Factors in Time-Like region
• Model independent analysis of polarization effects in elastic electron deuteron scattering in presence of two--photon exchange
• Two-photon exchange and elastic scattering of electrons/positrons on the proton. (Proposal for an experiment at VEPP-3)
• Search for two photon exchange from $e^{+}+e^{-}\to p+\bar{p}+\gamma$ data
• Charge asymmetry for electron (positron)-proton elastic scattering at large angle
• Observables in elastic electron-deuteron scattering with two-photon exchange
• On radiative corrections for unpolarized electron proton elastic scattering
• Model independent study of massive lepton elastic scattering on the proton, beyond the Born approximation
• Updated analysis of recent results on electron and positron elastic scattering on proton
• Form factor ratio from unpolarized elastic electron proton scattering
• The two photon exchange amplitude in $ep$ and $e\mu$ elastic scattering: a comparison
• Two-photon exchange: myth and history
• General analysis of two--photon exchange in elastic electron--${}^{4}He$ scattering and $e^{+}+e^{-}\to {\pi }^{+}+{\pi }^{-}.$
• Radiative corrections in proton--antiproton annihilation to electron-positron and their application to the PANDA experiment
• From theory to experiment: hadron electromagnetic form factors in space-like and time-like regions