Chiral extrapolation of nucleon magnetic moments at next-to-leading-order

Abstract

Nucleon magnetic moments display a rich nonanalytic dependence on the quark mass in both quenched and full QCD. They provide a forum for a detailed examination of the connection between quenched and full QCD made possible through the formalism of finite-range regularized chiral effective field theory. By defining meson-cloud and core contributions through the careful selection of a regularization scale, one can correct the meson cloud of quenched QCD to make full QCD predictions. Whereas past success is based on unquenching the leading-order loop contributions, here we extend and test the formalism including next-to-leading-order loop contributions. We discuss the subtleties associated with working at next-to-leading order and illustrate the role of higher-order corrections.

Electromagnetic form factors of octet baryons with the nonlocal chiral effective theory

“…An alternative regularization method, namely finite-range regularization (FRR) has been proposed. Inspired by quark models that account for the finite-size of the nucleon as the source of the pion cloud, effective field theory with FRR has been widely applied to extrapolate lattice data of vector meson mass, magnetic moments, magnetic form factors, strange form factors, charge radii, first moments of GPDs, nucleon spin, etc., [15][16][17][18][19][20][21][22][23][24].…”

Strange form factors of the nucleon with a nonlocal chiral effective Lagrangian

“…When vector mesons are included, the result is close to the experiments with Q 2 less than 0.4 GeV 2 [21].An alternative regularization method, namely finite-range-regularization (FRR) has been proposed. Inspired by quark models that account for the finite-size of the nucleon as the source of the pion cloud, effective field theory with FRR has been widely applied to extrapolate the vector meson mass, magnetic moments, magnetic form factors, strange form factors, charge radii, first moments of GPDs, nucleon spin, etc [22][23][24][25][26][27][28][29][30][31][32][33][34][35][36][37]. In the finite-range-regularization, there is no cut for the energy integral.…”

Pauli form factors of electron and muon in nonlocal quantum electrodynamics

“…We should mention that the regulator is not introduced phenomenologically to deal with the divergence. This is different from the original finite-range-regularization [21][22][23][24][25][26][27][28][29][30][31][32][33][34][35][36]. The regulator is naturally generated from the nonlocal Lagrangian with the naive idea that the interaction between photon and lepton does not necessary take place at one point.…”