Scaling and Topological Charge of a Fixed Point Action for $SU(2)$ Gauge   Theory
  We construct a few parameter approximate fixed point action for SU(2) pure gauge theory and subject it to scaling tests, via Monte Carlo simulation. We measure the critical coupling for deconfinement for lattices of temporal extent $N_t=2$, 3, 4, the torelon mass at fixed physical volume, and the string tension (and heavy quark potential) from Wilson loops. We calculate the topological susceptibility using inverse blocking and show that it scales over the observed range of lattice spacings. 
Thomas DeGrand, Anna Hasenfratz, Decai Zhu