We classify all strong-interaction contributions to all four-lepton processes through one loop in electroweak SU2×U1 and to all orders in strong interactions. We show that those parts which are not reliably calculated in perturbative QCD are all related to a certain integral over the total cross section for e+e-hadrons at low energies. We evaluate this integral for the most recent data and find that, for most four-lepton processes of interest, it is dominated by the timelike q2 region from 1 to 100 GeV2. We show that the associated theoretical strong-interaction uncertainty is a factor of 2 smaller than previously published estimates. We give the strong-interaction contribution and associated theoretical uncertainty for future SLAC, CERN, and Fermilab precision experiments and show that the theoretical uncertainty is quite small, thus allowing precision tests of the electroweak theory at the one-loop level. © 1987 The American Physical Society.
STRONG-INTERACTION CONTRIBUTIONS TO ONE-LOOP LEPTONIC PROCESSES / B. W., Lynn; Penso, Gianni; C., Verzegnassi. - In: PHYSICAL REVIEW D. - ISSN 0556-2821. - 35:1(1987), pp. 42-50. [10.1103/physrevd.35.42]
STRONG-INTERACTION CONTRIBUTIONS TO ONE-LOOP LEPTONIC PROCESSES
PENSO, Gianni;
1987
Abstract
We classify all strong-interaction contributions to all four-lepton processes through one loop in electroweak SU2×U1 and to all orders in strong interactions. We show that those parts which are not reliably calculated in perturbative QCD are all related to a certain integral over the total cross section for e+e-hadrons at low energies. We evaluate this integral for the most recent data and find that, for most four-lepton processes of interest, it is dominated by the timelike q2 region from 1 to 100 GeV2. We show that the associated theoretical strong-interaction uncertainty is a factor of 2 smaller than previously published estimates. We give the strong-interaction contribution and associated theoretical uncertainty for future SLAC, CERN, and Fermilab precision experiments and show that the theoretical uncertainty is quite small, thus allowing precision tests of the electroweak theory at the one-loop level. © 1987 The American Physical Society.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.