Related papers: Two-photon exchange at low Q^2
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…
We revisit the question of the contributions of two-photon exchange with $\Delta(1232)$ excitation to the electron-proton scattering in a hadronic model. Three improvements over the previous calculations are made, namely, correct vertex…
We present an improved evaluation of the two-photon exchange correction to the unpolarized lepton-proton elastic scattering process at very low-energies relevant to the MUSE experiment, where only the dominant intermediate elastic proton is…
A new form of two-photon exchange(TPE) effect is studied to explain the discrepancy between unpolarized and polarized experimental data in elastic $ep$ scattering. The mechanism is based on a simple idea that apart from the usual TPE…
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…
We investigate the two-photon corrections to the process $p\bar{p} \to e^+e^-$ at large momentum transfer, aimed to access the time-like nucleon form factors. We estimate the two-photon corrections using a hard rescattering mechanism, which…
Modern experiments with heavy ion-leptons collisions open the possibility to measure the deviation of cross section of small angles electron(positron)-ion elastic scattering from the Rutherford formula due to multiple virtual photons…
We investigate the effect of high order radiative corrections in unpolarized electron proton elastic scattering and compare with the calculations at lowest order, which are usually applied to experimental data. We show that higher order…
The proton elastic form factor ratio can be measured either via Rosenbluth separation in an experiment with unpolarized beam and target, or via the use of polarization degrees of freedom. However, data produced by these two approaches show…
We reanalyze the most recent data on elastic electron proton scattering. We look for a deviation from linearity of the Rosenbluth fit to the differential cross section, which would be the signature of the presence of two photon exchange.…
The contribution of the box and crossed two-pion-exchange diagrams to proton-proton scattering at 90$^{\circ}_{c.m.}$ is calculated in the laboratory momentum range up to 12 GeV/c. Relativistic form factors related to the nucleon and pion…
We report on precision measurements of the elastic cross section for electron-proton scattering performed in Hall C at Jefferson Lab. The measurements were made at 28 unique kinematic settings covering a range in momentum transfer of 0.4…
Using a general parametrization of the spin structure of the matrix element for the elastic $e^-+^4He$ scattering and for the annihilation $e^++e^-\to \pi^++\pi^-$ reactions in terms of two complex amplitudes, we derive general properties…
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…
The elastic and inelastic high--energy small--angle electron--positron scattering is considered. All radiative corrections to the cross--section with the relative accuracy $\delta\sigma/ \sigma = 0.1 \% $ are explicitly taken into account.…
We discuss the elastic ed scattering beyond Born approximation. It is shown that the reaction amplitude contains six generalized form factors, but only three linearly independent combinations of them (we call them generalized charge,…
In this note we give arguments in favor of the statement that the contribution of the box diagram calculated for electron muon elastic scattering can be considered an upper limit to electron proton scattering. As an exact QED calculation…
We derive from first principles, as the C-invariance of the electromagnetic interaction and the crossing symmetry, the general properties of two-photon exchange in electron-proton elastic scattering. We show that the presence of this…
Structure functions and polarization observables in elastic scattering of longitudinally polarized electron on polarized deuteron are considered within approximation of one-photon + two-photon exchange. It is shown that contribution of…
We discuss the target and beam normal spin asymmetries in elastic electron-nucleon scattering which depend on the imaginary part of two-photon exchange processes between electron and nucleon. In particular, we estimate these transverse spin…