English

Two-photon exchange correction in elastic lepton-proton scattering

High Energy Physics - Phenomenology 2018-07-04 v1 Nuclear Experiment Nuclear Theory

Abstract

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 πN\pi N intermediate state contributions are accounted for in the region of small momentum transfer Q2<1 GeV2Q^2 < 1~\mathrm{GeV}^2 based on the available data input. The novel methods of analytical continuation allow us to exploit the MAMI form factor data and the MAID parameterization for the pion electroproduction amplitudes as input in the calculation. The results are compared to the recent CLAS, VEPP-3 and OLYMPUS data as well as to the full two-photon exchange correction in the near-forward approximation, which is based on the Christy and Bosted unpolarized structure functions fit. Additionally, predictions are given for a forthcoming muon-proton scattering experiment.

Keywords

Cite

@article{arxiv.1806.01627,
  title  = {Two-photon exchange correction in elastic lepton-proton scattering},
  author = {Oleksandr Tomalak},
  journal= {arXiv preprint arXiv:1806.01627},
  year   = {2018}
}

Comments

12 pages, 8 figures, version published in Few-Body Syst. 59, 87 (2018)

R2 v1 2026-06-23T02:19:32.928Z