Leading logarithms in the anomalous sector of two-flavour QCD

Abstract

We add the Wess-Zumino-Witten term to the N = 3 massive nonlinear sigma model and study the leading logarithms in the anomalous sector. We obtain the leading logarithms to six loops for pi(0) -> gamma*gamma* and to five loops for y*pi pi pi.

In addition we extend the earlier work on the mass and decay constant to six loops and the vector form factor to five loops. We present numerical results for the anomalous processes and the vector form factor.

In all cases the series are found to converge rapidly.

Keywords

• Renormalization group evolution of parameters
• Spontaneous and radiative symmetry breaking
• Chiral Lagrangians
• Anomalous processes