|DATE||November 16 (Thu), 2017|
|TITLE||One-loop BPS amplitudes in heterotic flux vacua|
|ABSTRACT||We compute the new supersymmetric index of a large class of heterotic compactifications with torsion, corresponding to principal two-torus bundles over warped K3 surfaces
with H-flux. Starting from a UV description as a (0,2) gauged linear sigma-model with torsion, we use supersymmetric localization techniques to provide an explicit expression
of the index as a sum over the Jeffrey-Kirwan residues of the one-loop determinant. We then propose a geometrical formula that gives the new supersymmetric index in terms of bundle data, regardless of any particular choice of underlying two-dimensional theory. I may also briefly discuss some application to the computation of the one-loop
corrections to some BPS-saturated amplitudes.