Estiamte of the two-photon exchange effect on deuteron electromagnetic form factors

The corrections of two-photon exchange on deuteron electromagnetic form factors are estimated based on an effective Lagrangian approach. Numerical results for the form factors $G_{C,M,Q}$ of the deuteron with the corrections are compared to its empirical ones. Moreover, the two new form factors, due to the two-photon exchange, are analyzed. Possible way to test the two-photon exchange corrections to the deuteron form factors is discussed.Comment: 17 pages, 10 figure

Two-photon Exchange Corrections to Single Spin Asymmetry of Neutron and 3^3He

In a simple hadronic model, the two-photon exchange contributions to the single spin asymmetries for the nucleon and the $^3$He are estimated. The results show that the elastic contributions of two-photon exchange to the the single spin asymmetries for the nucleon are rather small while those for the $^3$He are relatively large. Besides the strong angular dependence, the two-photon contributions to the single spin asymmetry for the $^3$He are very sensitive to the momentum transfer.Comment: 11 pages, 8 figure