Contributions to the nucleon form factors from bubble and tadpole diagrams

TL;DR

This paper investigates nucleon electromagnetic and strange form factors using a nonlocal chiral effective theory, highlighting the impact of bubble and tadpole diagrams on the results and their agreement with experimental data.

Contribution

It introduces the inclusion of bubble and tadpole diagrams in the calculation of nucleon form factors within a nonlocal chiral effective theory.

Findings

Electromagnetic form factors remain close to previous results with proper low energy constants.

Strange form factors increase in magnitude when bubble and tadpole diagrams are included.

Results are consistent with experimental measurements.

Abstract

The nonlocal chiral effective theory is applied to investigate the electromagnetic and strange form factors of nucleon. The bubble and tadpole diagrams are included in the calculation. With the contributions from bubble and tadpole diagrams, the obtained electromagnetic form factors are close to the results without these contributions as long as the low energy constants $c_1$ and $c_2$ are properly chosen, while the magnitudes of strange form factors become larger. Both the electromagnetic and strange form factors are still in good agreement with the experimental data.