Strange form factors of nucleon with nonlocal chiral effective Lagrangian

Abstract: The strange form factors of nucleon are studied with the nonlocal chiral effective Lagrangian. One loop contributions from both octet and decuplet intermediate states are included. The relativistic regulator is obtained by the nonlocal Lagrangian where the gauge link is introduced to guarantee the local gauge symmetry. With the kaon loop, the calculated charge form factor is positive, while the magnetic form factor is negative. The strange magnetic moment is $-0.041^{+0.012}_{-0.014}$ with $\Lambda=0.9 \pm 0.1$ determined from the nucleon electromagnetic form factors. Our results are comparable with the recent lattice simulation.