Topological Amplitudes in Heterotic Strings with Wilson Lines

Understand

We consider d=4, N=2 compactifications of heterotic strings with an arbitrary number of Wilson lines.

• In particular, we focus on known chains of candidate heterotic/type II duals.
• We give closed expressions for the topological amplitudes F^g in terms of automorphic forms of SO(2+k,2,Z), and find agreement with the geometric data of the dual K3 fibrations wherever those are known.