par Abreu, Paulo;Bertrand, Daniel ; [et al.]
Référence Zeitschrift für Physik. C, Particles and fields, 72, page (31-38)
Publication Publié, 1996
Article révisé par les pairs
Résumé : The interference between initial and final state radiation in the process e+e-→μ+μ- at √s≈MZ has been studied by measuring the forward-backward asymmetry as a function of the acoplanarity angle between the final state muons. The interference is expected to be sensitive to the space-time separation of the initial and final state radiation. The measured asymmetry distribution has been compared to theoretical predictions using the koralz generator, with and without {Mathematical expression} interference. The magnitude of the interference between initial and final state radiation was found to be of the order predicted and to follow the expected distribution. Using the theoretical predictions, a value of {Mathematical expression} has been extracted. The interpretation of this result is discussed. There is an additional uncertainty in the estimate of ΓZ from as yet uncalculated higher order interference terms. By assuming a value of ΓZ consistent with the world average, the data were used to estimate the size of these uncalculated corrections. © 1996 Springer-Verlag.