Related papers: Effect of two-boson exchange on parity-violating e…
Parity violating asymmetry in inclusive scattering of longitudinally polarized electrons by unpolarized protons with $\pi^0$ or $\pi^+$ meson production, is calculated as a function of the momentum transfer squared $Q^2$ and the total…
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…
We use a relativistic model of meson-exchange currents to compute the proton-neutron and proton-proton yields in $(e,e')$ scattering from $^{12}$C in the 2p-2h channel. We compute the response functions and cross section with the…
We study the phenomenon of parton-hadron duality in both polarised and unpolarised electron proton scattering using the HERMES and the Jefferson Lab data, respectively. In both cases we extend a systematic perturbative QCD based analysis to…
Elastic scattering of relativistic electrons from the nucleon yields Lorentz invariant form factors that describe the fundamental distribution of charge and magnetism. The spatial dependence of the nucleon's charge and magnetism is…
In the one-photon exchange approximation, we analyze polarization effects in the elastic $\vec e \vec p \to e p$ and $ e \vec p \to \vec e p$ processes in the case when the spin quantization axes of a target proton at rest and an incident…
A new method of obtaining the strange form factors of the nucleon is presented, in which forward-angle parity-violating $\vec{e}p$ elastic scattering data is combined with $\nu p$ and $\bar{\nu} p$ elastic scattering data. The axial form…
Measurement of the neutral weak vector form factors of the nucleon provides unique access to the strange quark content of the nucleon. These form factors can be studied using parity-violating electron scattering. A comprehensive program of…
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 investigate the form factors for pseudoscalar-meson-photon transitions by means of dispersive QCD sum rules and demonstrate that most of the measurements done so far (in particular, those by BaBar for $\eta,$ $\eta',$ and $\eta_c$ and…
The two-photon-exchange (TPE) effects in the process $e^+e^- \rightarrow \pi^+\pi^-$ at large momentum transfer are discussed within the perturbative QCD (pQCD). The contributions from the twist-2 and twist-3 distribution amplitudes (DAs)…
Parity violation in elastic electron-nucleon scattering is studied with the basic goal of improving the understanding of electroweak hadronic structure with special emphasis on the strangeness content in the nucleon. Models for the…
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 effect of axial meson exchange on extraction of proton electromagnetic form factors in $ep$ scattering is calculated. Taking as an example $f_1(1285)$ meson exchange, it is quantitatively shown how it affects Rosenbluth and polarization…
The strangeness contribution to the vector and axial form factors of the proton is presented for momentum transfers in the range 0.45 < $Q^2$ < 1.0 GeV$^2$. The results are obtained via a combined analysis of forward-scattering…
We present a simple parameterization of the two-photon exchange amplitude in elastic electron-proton scattering, suitable for fast numerical evaluation.
The ratio of the electric and magnetic form factor of the proton, $\mu_p G_E^p/G_M^p$, has been measured for elastic electron-proton scattering with polarized beam and target up to four-momentum transfer squared, $Q^2=5.66$ (GeV/c)$^2$…
The ratio of electric to magnetic proton form factors G_E/G_M as measured in polarization transfer experiments shows a characteristic linear decrease with increasing momentum transfer Q^2. We present a simple argument how such a decrease…
Recently, there has been a significant amount of activity to try and understand the discrepancy between Rosenbluth and polarization transfer measurements of the proton form factors. It has been suggested that the standard use of plane-wave…
Recent experiments have discovered two exponents in the $pp$ elastic differential cross sections with two different slope parameters, of the order $(16-20)$~GeV$^{-2}$ and $(4-4.8)$~GeV$^{-2}$ in the regions $ -t \la 0.5 $~GeV$^2$ and $ -t…