Electric Polarizability of Neutral Hadrons from Lattice QCD

TL;DR

This study uses lattice QCD simulations to calculate the electric polarizability of various neutral hadrons, comparing results from different fermion actions and with experimental data for the neutron.

Contribution

First lattice QCD calculation of electric polarizability for multiple neutral hadrons using two different fermion actions for validation.

Findings

Neutron polarizability results agree with experimental data.

Consistent results obtained from two different lattice actions.

Electric polarizabilities measured for 10 different neutral hadrons.

Abstract

By simulating a uniform electric field on a lattice and measuring the change in the rest mass, we calculate the electric polarizability of neutral mesons and baryons using the methods of quenched lattice QCD. Specifically, we measure the electric polarizability coefficient from the quadratic response to the electric field for 10 particles: the vector mesons $\rho^0$ and $K^{*0}$; the octet baryons n, $\Sigma^0$, $\Lambda_{o}^{0}$, $\Lambda_{s}^{0}$, and $\Xi^0$; and the decouplet baryons $\Delta^0$, $\Sigma^{*0}$, and $\Xi^{*0}$. Independent calculations using two fermion actions were done for consistency and comparison purposes. One calculation uses Wilson fermions with a lattice spacing of $a=0.10 $fm. The other uses tadpole improved L\"usher-Weiss gauge fields and clover quark action with a lattice spacing $a=0.17 $fm. Our results for neutron electric polarizability are compared to experiment.