A differential model for B-type Landau-Ginzburg theories

We describe a mathematically rigorous differential model for B-type open-closed topological Landau-Ginzburg theories defined by a pair $(X,W)$, where $X$ is a non-compact K"ahlerian manifold with holomorphically trivial canonical line bundle and $W$ is a complex-valued holomorphic function defined on $X$ and whose critical locus is compact but need not consist of isolated points. We also show how this construction specializes to the case when $X$ is Stein and $W$ has finite critical set, in which case one recovers a simpler mathematical model.