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arXiv · hep-ph/9706542

Low-Energy Constraints on New Physics Revisited

S. Dawson·S. Alam·R. Szalapski
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Abstract

It is possible to place constraints on non-Standard-Model gauge-boson self-couplings and other new physics by studying their one-loop contributions to precisely measured observables. We extend previous analyses which constrain such nonstandard couplings, and we present the results in a compact and transparent form. Particular attention is given to comparing results for the light-Higgs scenario, where nonstandard effects are parameterized by an effective Lagrangian with a linear realization of the electroweak symmetry breaking sector, and the heavy-Higgs/strongly interacting scenario, described by the electroweak chiral Lagrangian. The constraints on nonstandard gauge-boson self-couplings which are obtained from a global analysis of low-energy data and LEP/SLC measurements on the Z pole are updated and improved from previous studies. Replaced version: tables and figures of Section VIb recalculated. There were roundoff problems, especially in Fig. 8. Text unchanged.

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S. Dawson, S. Alam, R. Szalapski. 1997-09-11. Low-Energy Constraints on New Physics Revisited. https://doi.org/10.1103/physrevd.57.1577

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