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The Minimal Set of Electroweak Precision Parameters

G. Cacciapaglia·C. Csáki·G. Marandella·A. Strumia
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Abstract

We present a simple method for analyzing the impact of precision electroweak data above and below the Z-peak on flavour-conserving heavy new physics. We find that experiments have probed about ten combinations of new physics effects, which to a good approximation can be condensed into the effective oblique parameters Shat, That, Uhat, V, X, W, Y (we prove positivity constraints W, Y >= 0) and three combinations of quark couplings (including a distinct parameter for the bottom). We apply our method to generic extra Z' vectors.

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G. Cacciapaglia, C. Csáki, G. Marandella, A. Strumia. 2006-04-12. The Minimal Set of Electroweak Precision Parameters. https://doi.org/10.1103/physrevd.74.033011

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