Two-Photon-Exchange effect in $ep\to en{\pi }^{+}$ at small $-t$ with the hadronic model and dispersion relation approach

Qian-Qian Guo, Hai-Qing Zhou

In this work, the two-photon-exchange (TPE) effect in $ep\to en{\pi }^{+}$ at small $-t$ is discussed. In the previous work, the TPE contribution with one $\pi$ intermediate state i…