Two-photon Exchange Corrections at Large Momentum Transfer Revised
Year: 2025
Type: article
Abstract: Motivated by experimental data at large momentum transfer, we update the analysis of the two-photon exchange effect in the electron–nucleon scattering using the effective field theory formalism. Our approach is suitable for describing the hard \(s\sim |t|\sim |u|\gg \mit {\Lambda }^2\) region, where the hadronic model calculations are not accurate enough. We improve the estimates of various long-range matrix elements and discuss the obtained numerical effects for the unpolarised elastic cross section. Assuming a linear behaviour of the reduced cross section with respect to the photon polarisation, we show that the obtained description allows us to resolve the form factor discrepancy for \(Q^2=2.5\)–3.5 GeV\(^2\). However, the effect obtained is quite small for higher values of \(Q^2\). It is possible that nonlinear effects may be important in understanding the discrepancy in this region. Estimates of the elastic electron–neutron cross section in the region of \(Q^2=2.5\)–3.5 GeV\(^2\) are also performed. The obtained TPE effects are sufficiently large and must be taken into account. Abstract Published by the Jagiellonian University 2025 authors
Source: Acta Physica Polonica B
Author: N. Kivel
Institution: Technical University of Munich
Language: English
Subfield: Nuclear and High Energy Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: diamond
OpenAlex ID: W4409504677