Magnetic field inside of a nucleon and the quark-Zeeman effect

Abstract

Zeeman effect has been an invaluable tool for the detection and measurement of the effects of a magnetic field on the internal behavior of atoms and nuclei. Along with M\"{o}ssbauer effect, it has been used to determine the magnitude of the magnetic field present in nuclei of atoms but has not been detected inside nucleons so far. In this work, we present a possible signature of the Zeeman-like effect in nucleons that one can extract from the parton distributions with the use of statistical models and Fermi-Dirac distribution. These effects in turn---if electromagnetically dominated---predict the presence of magnetic fields of an unprecedented magnitude inside protons.