Baryon magnetic moments: Symmetries and relations

¹ Department of Quantum Physics and Astrophysics, and Institute of Cosmos Sciences, University of Barcelona, E-08028, Spain
² Institute for Nuclear Theory, University of Washington, Seattle, WA 98195, USA
³ Department of Physics, The City College of New York, New York, NY 10031, USA
⁴ Graduate School and University Center, The City University of New York, New York, NY 10016, USA
⁵ Justus-Liebig-Universität Gießen, Ludwigstraße 23, Gießen 35390, Germany
⁶ Department of Physics, University of Washington, Seattle, WA 98195, USA
⁷ Center for Theoretical Physics, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
⁸ Department of Physics, College of William and Mary, Williamsburg, VA 23187, USA
⁹ Jefferson Laboratory, 12000 Jefferson Avenue, Newport News, VA 23606, USA

^* Speaker, e-mail: btiburzi@ccny.cuny.edu

Published online: 26 March 2018

Abstract

Magnetic moments of the octet baryons are computed using lattice QCD in background magnetic fields, including the first treatment of the magnetically coupled ∑₀- ⋀ system. Although the computations are performed for relatively large values of the up and down quark masses, we gain new insight into the symmetries and relations between magnetic moments by working at a three-flavor mass-symmetric point. While the spinflavor symmetry in the large N_c limit of QCD is shared by the naïve constituent quark model, we find instances where quark model predictions are considerably favored over those emerging in the large N_c limit. We suggest further calculations that would shed light on the curious patterns of baryon magnetic moments.