Low energy effects for a family of Friedrichs models
arXiv:math/0604282
Abstract
A family of Friedrichs models with rank one perturbations associated to a system of two particles on the lattice is considered. The existence of a unique strictly positive eigenvalue below the bottom of the essential spectrum of for all nontrivial values under the assumption that has either a zero energy resonance (virtual level) or a threshold eigenvalue is proved. Low energy asymptotic expansion for the Fredholm determinant associated to family of Friedrichs models is obtained.
11 pages