Abstract
We evaluate the corrections of the two-photon exchange (TPE) process on the transition form factors. The contributions of the TPE process to are calculated in a hadronic model with the inclusion of only the elastic nucleon intermediate states, to estimate its effects on the multipoles at the peak. We find that TPE effects on are very small. and are also little affected at small . For , the TPE effects reach about near , depending on the model, MAID or SAID, used to emulate the data. For , the TPE effects decrease rapidly with increasing while growing with increasing to reach with at . Sizeable TPE corrections to and found here point to the need to include TPE effects in the multipole analysis in the region of high and small . The TPE corrections to and obtained in our hadronic calculation are compared with those obtained in a partonic calculation for moderate momentum transfer of .
- Received 15 April 2017
- Revised 6 September 2017
DOI:https://doi.org/10.1103/PhysRevC.96.055210
©2017 American Physical Society