Colorful SU(2) center vortices in the continuum and on the lattice
  The spherical vortex as introduced in [Phys. Rev. D77, 014515 (2008)] is generalized. A continuum form of the spherical vortex is derived and investigated in detail. The discrepancy between the gluonic lattice topological charge and the index of the lattice Dirac operator described in previous papers is identified as a discretization effect. The importance of the investigations for Monte Carlo configurations is discussed. 
Thomas Schweigler, Roman H\"ollwieser, Manfried Faber and Urs M.   Heller
hep-lat