Electromagnetic polarizabilities: Lattice QCD in background fields

Conference · Sun Apr 01 04:00:00 EDT 2012 · AIP Conf. Proc.

DOI:https://doi.org/10.1063/1.3700501· OSTI ID:1038757

Chiral perturbation theory makes definitive predictions for the extrinsic behavior of hadrons in external electric and magnetic fields. Near the chiral limit, the electric and magnetic polarizabilities of pions, kaons, and nucleons are determined in terms of a few well-known parameters. In this limit, hadrons become quantum mechanically diffuse as polarizabilities scale with the inverse square-root of the quark mass. In some cases, however, such predictions from chiral perturbation theory have not compared well with experimental data. Ultimately we must turn to first principles numerical simulations of QCD to determine properties of hadrons, and confront the predictions of chiral perturbation theory. To address the electromagnetic polarizabilities, we utilize the background field technique. Restricting our attention to calculations in background electric fields, we demonstrate new techniques to determine electric polarizabilities and baryon magnetic moments for both charged and neutral states. As we can study the quark mass dependence of observables with lattice QCD, the lattice will provide a crucial test of our understanding of low-energy QCD, which will be timely in light of ongoing experiments, such as at COMPASS and HI gamma S.

• Research Organization: Thomas Jefferson National Accelerator Facility, Newport News, VA (United States)
• Sponsoring Organization: USDOE Office of Science (SC)
• DOE Contract Number: AC05-06OR23177
• OSTI ID: 1038757
• Report Number(s): JLAB-THY-11-1455; DOE/OR/23177-3706; arXiv:1108.1698
• Conference Information: Journal Name: AIP Conf. Proc. Journal Volume: 1441
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
BARYONS
ELECTRIC FIELDS
HADRONS
KAONS
MAGNETIC FIELDS
MAGNETIC MOMENTS
NUCLEONS
PERTURBATION THEORY
PIONS
QUANTUM CHROMODYNAMICS
QUARKS