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تسجيل مستخدم جديدSubtracted dispersion relation formalism for the two-photon exchange correction to elastic electron-proton scattering: comparison with data
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We apply a subtracted dispersion relation formalism with the aim to improve predictions for the two-photon exchange corrections to elastic electron-proton scattering observables at finite momentum transfers. We study the formalism on the elastic contribution, and make a detailed comparison with existing data for unpolarized cross sections as well as polarization transfer observables.
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We review recent theoretical and experimental progress on the role of two-photon exchange (TPE) in electron-proton scattering at low to moderate momentum transfers. We make a detailed comparison and analysis of the results of competing experiments on
the ratio of e+p to e-p elastic scattering cross sections, and of the theoretical calculations describing them. A summary of the current experimental situation is provided, along with an outlook for future experiments.
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 angular dep
endence at fixed $Q^2$. This is significant for the Rosenbluth technique for determining the ratio of the electric and magnetic form factors of the proton at high $Q^2$, and partly reconciles the apparent discrepancy with the results of the polarization transfer technique.
A detailed study of two-photon exchange in unpolarized and polarized elastic electron--nucleon scattering is presented, taking particular account of nucleon finite size effects. Contributions from nucleon elastic intermediate states are found to have
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We report new precision measurements of the elastic electron-proton scattering cross section for momentum transfer squared (Q$^2$) up to 15.75~gevsq. These data allow for improved extraction of the proton magnetic form factor at high Q$^2$ and nearly
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We perform a fit of the real Compton scattering (RCS) data below pion-production threshold to extract the electric ($alpha_{E1}$) and magnetic ($beta_{M1}$) static scalar dipole polarizabilities of the proton, using fixed-$t$ subtracted dispersion re
lations and a bootstrap-based fitting technique. The bootstrap method provides a convenient tool to include the effects of the systematic errors on the best values of $alpha_{E1}$ and $beta_{M1}$ and to propagate the statistical errors of the model parameters fixed by other measurements. We also implement various statistical tests to investigate the consistency of the available RCS data sets below pion-production threshold and we conclude that there are not strong motivations to exclude any data point from the global set. Our analysis yields $alpha_{E1} = (12.03^{+0.48}_{-0.54})times 10^{-4} text{fm}^3$ and $beta_{M1} = (1.77^{+0.52}_{-0.54})times 10^{-4} text{fm}^3$, with p-value $= 12%$.
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