2023/07/17 by Lee, Frank X., Wilcox, Walter, Alexandru, Andrei +1
#FOS: Physical sciences #High Energy Physics - Lattice (hep-lat) #Nuclear Theory (nucl-th)
paper · doi:10.48550/arxiv.2307.08620
Electromagnetic dipole polarizabilities are fundamental properties of a hadron that represent its resistance to deformation under external fields. For a charged hadron, the presence of acceleration and Landau levels complicates the isolation of its deformation energy in the conventional background field method. In this work, we explore a general method based on four-point functions in lattice QCD that takes into account all photon, quark and gluon interactions. The electric polarizability (αE) has been determined from the method in a previous proof-of-principle simulation. Here we focus on the magnetic polarizability (βM) using the same quenched Wilson action on a 243× 48 lattice at β=6.0 with pion mass from 1100 to 370 MeV. The results from the connected diagrams show a large cancellation between the elastic and inelastic contributions, leading to a relatively small and negative value for βM consistent with chiral perturbation theory. We also discuss the mechanism for αE+βM from combining the two studies.