Partition functions for equivariantly twisted N=2 gauge theories on toric Kahler manifolds

We consider N = 2 supersymmetric pure gauge theories on toric Kahler manifolds, with particular emphasis on CP2. By choosing a vector generating a U(1) action inside the torus of the manifold, we construct equivariantly twisted theories. Then, using localization, we compute their supersymmetric partition functions. As expected, these receive contributions from a classical, a one-loop, and an instanton term. It turns out that the one-loop term is trivial and that the instanton contributions are localized at the fixed points of the U(1). In fact the full partition function can be re-written in a factorized form with contributions from each of the fixed points. The full significance of this is yet to be understood.