Abstract
In this work, we improve on and extend to low- and high- values the extractions of the two-photon-exchange (TPE) amplitudes and the ratio using world data on electron-proton elastic scattering cross section with an emphasis on data covering the high-momentum region, up to , to better constrain the TPE amplitudes in this region. We provide a new parametrization of the TPE amplitudes, along with an estimate of the fit uncertainties. We compare the results to several previous phenomenological extractions and hadronic TPE predictions. We use the new parametrization of the TPE amplitudes to extract the ratio , and then compare the results to previous extractions, several theoretical calculations, and direct measurements at .
- Received 4 February 2018
DOI:https://doi.org/10.1103/PhysRevC.97.045201
©2018 American Physical Society