QCD coupling below 1 GeV from quarkonium spectrum
| dc.creator | Baldicchi, M. | |
| dc.creator | Nesterenko, A. V. | |
| dc.creator | Prosperi, G. M. | |
| dc.creator | Simolo, C. | |
| dc.date | 2007-05-11 | |
| dc.date | 2007-08-20 | |
| dc.date.accessioned | 2026-07-07T11:20:36Z | |
| dc.date.available | 2026-07-07T11:20:36Z | |
| dc.description | In this paper we extend the work synthetically presented in Ref.[1] and give theoretical details and complete tables of numerical results. We exploit calculations within a Bethe-Salpeter (BS) formalism adjusted for QCD, in order to extract an ``experimental'' strong coupling α_s^{exp}(Q^2) below 1 GeV by comparison with the meson spectrum. The BS potential follows from a proper ansatz on the Wilson loop to encode confinement and is the sum of a one-gluon-exchange and a confinement terms. Besides, the common perturbative strong coupling is replaced by the ghost-free expression α_E(Q^2) according to the prescription of Analytic Perturbation Theory (APT). The agreement of α_s^{exp}(Q^2) with the APT coupling α_E(Q^2) turns out to be reasonable from 1 GeV down to the 200 MeV scale, thus confirming quantitatively the validity of the APT prescription. Below this scale, the experimental points could give a hint on the vanishing of α_s(Q^2) as Q approaches zero. This infrared behaviour would be consistent with some lattice results and a ``massive'' generalization of the APT approach. As a main result, we claim that the combined BS-APT theoretical scheme provides us with a rather satisfactory correlated understanding of very high and rather low energy phenomena from few hundreds MeV to few hundreds GeV. | |
| dc.description | Preliminary revision. Typos corrected, comments and references added | |
| dc.identifier | https://arxiv.org/abs/0705.1695 | |
| dc.identifier | http://arxiv.org/abs/0705.1695 | |
| dc.identifier | Phys.Rev.D77:034013,2008 | |
| dc.identifier | doi:10.1103/PhysRevD.77.034013 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/194010 | |
| dc.subject | High Energy Physics - Phenomenology | |
| dc.title | QCD coupling below 1 GeV from quarkonium spectrum | |
| dc.type | text |