Archive of historical materials
Note: Magnetic Moment of Proton
OU1934-B8 (3 pages) Date: Not indicated
This is a calculation note in which Yukawa attempted to explain why the observed magnetic moment of protons was significantly different from the magnetic moment determined on the hypothesis that protons were simply particles described by a Dirac field. Yukawa thought of explaining using the U particle or U field (now known as a meson) proposed previously by himself. Protons and neutrons release and acquire U particles and change their places. Yukawa thought this interaction might alter the magnetic moments of protons and neutrons.
It is known today that a proton is composed primarily of three quarks and the magnetic moment of a proton is the sum of the magnetic moments of the three quarks. (Written by Yutaka Hosotani)