0000000000160616
AUTHOR
R. Buchert
showing 3 related works from this author
TheA 1-and the ϕ-meson in QCD
1993
Recently we used a method of stable analytic extrapolation to test whether strictly local duality between the asymptotic and the resonance region, which is believed to be valid in QCD, appears already at the present stage of QCD calculations. Probing the QCD ϱ-amplitude, we found a prominent bump structure in the resonance region, i.e. a rather direct evidence for the validity of local duality. In the present paper we confirm and extend this result by giving two further applications, theA1-meson and the ϕ-meson. While we do not meet theA1, as was to be expected since other sum rules can not separate it from the continuum, too, the extrapolation of the ϕ-amplitude leads to an enormous bump. …
A new approach to the ϱ-meson in QCD
1993
We examine whether strict local duality between the asymptotic and the resonance region, which is of course believed to be valid in QCD, already appears at the present stage of QCD calculations. For this purpose we propose a new method of stable analytic extrapolation which follows the spirit of a previously used method but has essential advantages compared to the original formulation. A careful analysis of the present QCD ϱ-amplitude leads indeed to a prominent bump structure in the resonance region. This is a first evidence for the validity of strictly local duality within QCD.
The generation of the ϱ-resonance by QCD
1992
By showing that the imaginary part of a suitable QCD amplitude, after extrapolation up to the cut, exhibits indeed a prominent bump structure where the ϱ-resonance is expected to be, a rather direct indication for the generation of the ϱ-resonance by QCD is given. This is achieved by using a mathematically rigorous method of stable analytic extrapolation, based on the theory of maximally converging sequences of polynomials and the application of conformal mappings.