Year: 1998
Type: article
Abstract: We include the full second-order corrections to the static QCD potential in the analysis of the $t\overline{t}$ threshold cross section. There is an unexpectedly large difference between the QCD potential improved by the renormalization-group equation in momentum space and the potential improved by the renormalization-group equation in coordinate space. This difference remains even at a fairly short distance $1/r\ensuremath{\simeq}100\mathrm{GeV}$ and its origin can be understood within perturbative QCD. We scrutinize the theoretical uncertainties of the QCD potential in relation to the $t\overline{t}$ threshold cross section. In particular there exists a theoretical uncertainty which limits our present theoretical accuracy of the $t\overline{t}$ threshold cross section at the peak to be $\ensuremath{\delta}{\ensuremath{\sigma}}_{\mathrm{peak}}/{\ensuremath{\sigma}}_{\mathrm{peak}}\ensuremath{\gtrsim}6%$ within perturbative QCD.
Authors: M. Jeżabek, J. H. Kühn, Y. Sumino, M. Peter, T. Teubner
Language: Latvian
Subfield: Nuclear and High Energy Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W326254451