Abstract
For a class of Feynman graphs Gn (single-loop diagrams with all internal diagonals), the p-space perturbation Landau singularity manifolds are shown to be formally of the same structure as the Källén Ξn(t) manifolds for the x-space axiomatic primitive domain. The boundary of the Landau manifold is then shown to be the (DANAD)′ manifold. The relationship between the (DANAD)′ and the Jost (DANAD) manifold is a precise generalization of what exists between the Fkl and Fkl surfaces of Källén and Wightman. Since the (DANAD)′ defines a natural domain of holomorphy, the axiomatic envelope of holomorphy cannot be expected to be continuable beyond (DANAD)′. This (DANAD)′ result furnishes a specific conjecture to part of the envelope of holomorphy.