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arXiv · 1712.02350

Better Higgs-CP Tests Through Information Geometry

Johann Brehmer·Felix Kling·Tilman Plehn·Tim M. P. Tait
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Abstract

Measuring the CP symmetry in the Higgs sector is one of the key tasks of the LHC and a crucial ingredient for precision studies, for example in the language of effective Lagrangians. We systematically analyze which LHC signatures offer dedicated CP measurements in the Higgs-gauge sector, and discuss the nature of the information they provide. Based on the Fisher information measure, we compare the maximal reach for CP-violating effects in weak boson fusion, associated ZH production, and Higgs decays into four leptons. We find a subtle balance between more theory-independent approaches and more powerful analysis channels, indicating that rigorous evidence for CP violation in the Higgs-gauge sector will likely require a multi-step process.

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Johann Brehmer, Felix Kling, Tilman Plehn, Tim M. P. Tait. 2017-12-06. Better Higgs-CP Tests Through Information Geometry. https://doi.org/10.1103/physrevd.97.095017

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