OPAL Collaboration (1999) Tests of the Standard Model and constraints on new physics from measurements of fermion-pair production at 183 GeV at LEP. European Physical Journal C: Particles and Fields, 6 (1). pp. 1-18. ISSN 1434-6044
Full text not available from this repository.Abstract
Cross-sections for hadronic, bb¯bb¯ and lepton pair final states in e+e−e+e− collisions at s√s =183 GeV, measured with the OPAL detector at LEP, are presented and compared with the predictions of the Standard Model. Forward-backward asymmetries for the leptonic final states have also been measured. Cross-sections and asymmetries are also presented for data recorded in 1997 at s√s =130 and 136 GeV. The results are used to measure the energy dependence of the electromagnetic coupling constant αemαem , and to place limits on new physics as described by four-fermion contact interactions or by the exchange of a new heavy particle such as a leptoquark, or of a squark or sneutrino in supersymmetric theories with R-parity violation.