Abstract
The method of analytic perturbation theory, which avoids the problem of ghost-pole-type singularities and gives a self-consistent description of both spacelike and timelike regions, is applied to describe the “light” Adler function corresponding to the nonstrange vector channel of the inclusive decay of the lepton. The role of threshold effects is investigated. The behavior of the quark-antiquark system near threshold is described by using a new relativistic resummation factor. It is shown that the method proposed leads to good agreement with the “experimental” Adler function down to the lowest energy scale.
- Received 21 February 2001
DOI:https://doi.org/10.1103/PhysRevD.64.016005
©2001 American Physical Society