相关论文: Two photon exchange amplitude with \pi N intermedi…

The details of the calculation of the two-boson exchange effects in the parity-violating elastic $ep$ scattering within a simple hadronic model, including both the nucleon and $\Delta(1232)$-resonance intermediate states, are presented. We…

We present a comprehensive study of two-boson exchange (TBE) corrections in parity-violating electron-proton elastic scattering. Within a hadronic framework, we compute contributions from box (and crossed box) diagrams in which the…

In this work, I improve on and extend to low and high $Q^2$ values the extractions of the $\varepsilon$ dependence of the real parts of the two-photon exchange (TPE) amplitudes relative to the magnetic form factor, as well as the ratio…

We study the leading electroweak corrections in the precision measurement of the strange form factors. Specifically, we calculate the two-boson-exchange (TBE), two-photon-exchange (TPE) plus $\gamma Z$-exchange ($\gamma Z$E), corrections…

We report on a new measurement of the beam transverse single spin asymmetry in electron-proton elastic scattering, $A^{ep}_{\perp}$, at five beam energies from 315.1 MeV to 1508.4 MeV and at a scattering angle of $30^{\circ} < \theta <…

We present the dispersion relation approach based on unitarity and analyticity to evaluate the two-photon exchange contribution to elastic electron-proton scattering. The leading elastic and first inelastic $\pi N$ intermediate state…

We calculate the two-photon exchange (TPE) corrections in the region where the kinematical variables describing the elastic $ep$ scattering are moderately large momentum scales relative to the soft hadronic scale. For such kinematics we use…

The resonances ($\eta_c,\chi_{c0,c2}$) contribution to two-photon exchange (TPE) effects in $e^+ e^- \leftrightarrow p \bar{p}$ is calculated in a simple hadronic model. The calculation shows the TPE contributions by resonance $\chi_{c2}$,…

We consider the relationship between P-wave pi-N scattering and the strength of the P-wave two-pion-exchange three-nucleon interaction (TPE3NI). We explain why effective theories that do not contain the delta resonance as an explicit degree…

Measurements of the ratio of the elastic form factors of the proton ($\mu_pG_E/G_M$) exhibit a strong discrepancy. Experiments using unpolarized beams and Rosenbluth separation to determine the form factors have found values of the ratio…

We extract two-photon exchange amplitudes for the elastic electron-proton scattering at Q^2=2.5 GeV^2 from the unpolarized cross-section and recent polarization transfer measurements. There are three independent amplitudes, but only one of…

Here we consider a contribution of Delta(1232) resonance to real photon radiative corrections for elastic $ep$-scattering. The effect is found to be small for past experiments to study unpolarized cross section as well as for the recent…

Two-photon exchange (TPE) contributions to elastic electron-proton scattering in the forward regime and in leading log $\sim t\ln|t|$ approximation in the momentum transfer $|t|$ are considered. The imaginary part of TPE amplitude in these…

We evaluate the two-photon exchange contribution to the $e N \to e \Delta(1232) \to e \pi N$ process at large momentum transfer with the aim of a precision study of the ratios of electric quadrupole (E2) and Coulomb quadrupole (C2) to the…

Employing the covariant baryon chiral perturbation theory, we calculate the leading and next-to-leading order two-pion exchange (TPE) contributions to $NN$ interaction up to order $O(p^3)$. We compare the so-obtained $NN$ phase shifts with…

We calculate the two-boson-exchange (TBE) corrections to the parity-violating asymmetry of the elastic electron-proton scattering in a simple hadronic model including the nucleon and the $\Delta(1232)$ intermediate states. We find that…

The discrepancy between proton electromagnetic form factors extracted using unpolarized and polarized scattering data is believed to be a consequence of two-photon exchange (TPE) effects. However, the calculations of TPE corrections have…

The presence of two photon exchange in $ep$ elastic scattering and in the crossed processes ($\bar p +p\leftrightarrow \ell^+ +\ell^-$, $\ell=e$ or $\mu$) is discussed in terms of three complex amplitudes which are functions of two…

The effects of multi-photon-exchange and other higher-order QED corrections on elastic electron-proton scattering have been a subject of high experimental and theoretical interest since the polarization transfer measurements of the proton…

We consider radiative corrections to polarization observables in elastic electron-proton scattering, in particular, for the polarization transfer measurements of the proton form factor ratio $\mu G_E/G_M$. The corrections are of two types:…