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arXiv · hep-ph/9508390

S-Matrix Approach to the $Z$ Line Shape

Arnd Leike·Joachim Rose·Tord Riemann
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Abstract

We analyze the $Z$ line shape assuming the existence of an analytic, unitary S-matrix. As an example, from hadron production at LEP we determine $M_{Z}=91.134 \pm 0.020 \pm 0.020 \: ({\rm LEP})$ GeV, $Γ_{Z}=2.506 \pm 0.018$ GeV. This is in accordance with earlier results after performing a shift of the $Z$ mass value of about $\frac{1}{2}Γ_Z^2/M_Z = 34$ MeV. The cross section and related observables may be described by a small number of additional degrees of freedom without relying on a specific field-theoretic model.

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Arnd Leike, Joachim Rose, Tord Riemann. 1995-08-29. S-Matrix Approach to the $Z$ Line Shape. https://doi.org/10.1016/0370-2693(91)90307-c

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