The topological susceptibility of SU(3) gauge theory near T_c
  We compute the topological susceptibility chi_t in SU(3) lattice gauge theory using fermionic methods based on the Atiyah-Singer index theorem. Near the phase transition we find a smooth crossover behavior for chi_t with values decreasing from (191(5) MeV)^4 to (100(5) MeV)^4 as we increase the temperature from 0.88 T_c to 1.31 T_c, showing that topological excitations exist far above T_c. Our study is the first large scale analysis of the topological susceptibility at high temperature based on the index theorem and the results agree well with field theoretical methods. 
Christof Gattringer, Roland Hoffmann and Stefan Schaefer (Regensburg)