Magnetic field induced anomalous pion couplings

Abstract

Effective pion-constituent quark couplings induced by relatively weak magnetic fields are calculated, being that they disappear in the vacuum. In particular, couplings to a scalar and a vector constituent quark currents are investigated. These couplings can correspond to a fluctuation of the neutral pion into a scalar quark-antiquark meson and to a vector meson respectively. Some possible phenomenological implications are discussed.

Figures (10)

• Figure 1: Constituent quark- pion interaction in a magnetic field: dashed line for pion, solid line for quark, wiggly lines with a dot for gluons, soft wiggly line for the magnetic field insertion.
• Figure 2: Neutral pion scalar form factor, Eq. \ref{['Fsppi']}, for on-shell quark and off-shell pion.
• Figure 3: Charged pion scalar form factor, Eq. \ref{['Fsppi']}, for on-shell quark and off-shell pion.
• Figure 4: Neutral pion vector form factor, Eq. \ref{['Fvppi']}, for on-shell quark and off-shell pion.
• Figure 5: Charged pion vector form factor, Eq. \ref{['Fvppi']}, for on-shell quark and off-shell pion.