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arXiv · 1610.04501

S-matrix approach to the Z resonance

T. Riemann
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Abstract

The proposed $e^+e^-$-collider FCC-ee aims at an unprecedented accuracy for $e^+e^-$ collisions into fermion pairs at the $Z$ peak, based on about $10^{13}$ events. The S-matrix approach to the $Z$ boson line shape allows the model-independent quantitative description of the reaction $e^+e^- \to {\bar f}f$ around the $Z$ peak in terms of few parameters, among them the mass $M_Z$ and width $\Gamma_Z$ of the $Z$-boson. While weak and strong corrections remain "black", a careful theoretical description of the photonic interactions is mandatory. I introduce the method and describe applications and the analysis tool SMATASY/ZFITTER.

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T. Riemann. 2016-10-14. S-matrix approach to the Z resonance. https://doi.org/10.5506/aphyspolb.46.2235

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