NSVZ scheme with the higher derivative regularization for N=1 SQED

Understand

The exact NSVZ relation between a $\beta$-function of ${\cal N}=1$ SQED and an anomalous dimension of the matter superfields is studied within the Slavnov higher derivative regularization approach.

• It is shown that if the renormalization group functions are defined in terms of the bare coupling constant, this relation is always valid.
• In the renormalized theory the NSVZ relation is obtained in the momentum subtraction scheme supplemented by a special finite renormalization.
• Unlike the dimensional reduction, the higher derivative regularization allows to fix this finite renormalization.