Topology with Dynamical Overlap Fermions
  We perform dynamical QCD simulations with $n_f=2$ overlap fermions by hybrid Monte-Carlo method on $6^4$ to $8^3\times 16$ lattices. We study the problem of topological sector changing. A new method is proposed which works without topological sector changes. We use this new method to determine the topological susceptibility at various quark masses. 
G. I. Egri, Z. Fodor, S. D. Katz, K.K. Szabo