Strange Magnetic Moment of The Nucleon from Lattice QCD

TL;DR

This paper computes the strange magnetic moment of the nucleon using lattice QCD techniques, providing a precise estimate of the strange quark contribution to nucleon magnetism.

Contribution

It introduces an improved stochastic method with error reduction techniques for calculating disconnected insertions in lattice QCD.

Findings

Strange magnetic moment estimated as G_M^s = -0.28 ± 0.10 μ_N.

Error reduction achieved by a factor of 2 using charge conjugation and hermiticity.

Method demonstrates effective calculation of strange quark contributions in nucleons.

Abstract

We calculate the strange magnetic moment of the nucleon on a quenched $16^3 \times 24$ lattice at $\beta = 6.0$, and with Wilson fermions at $\kappa$ = 0.148, 0.152, and 0.154. The strange quark contribution from the disconnected insertion is estimated stochastically by employing the $Z_2$ noise method. Using an unbiased subtraction along with the help of charge conjugation and hermiticity, we reduce the error by a factor of 2 with negligible overhead. Our result is $G_{M}^{s} = -0.28\pm0.10 \mu_{N}$.