Strong coupling expansion for the mass gap in SU(2) lattice gauge theory with mixed action

We perform a strong coupling expansion up to O(β⁷) for the mass-gap in SU(2) lattice gauge theory with mixed action. A novel feature of the strong coupling expansion is discussed. The strong coupling series appears to approach the scaling region more smoothly and Padé approximants become more stable than in the case with simple Wilson action. The region of validity of a recently proposed resummation of perturbation theory as applied to the determination of the asymptotic scaling behavior is investigated. Results of a strong coupling calculation for the heat kernel action, which is related to the mixed action for a special choice of parameters, are also reported.