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arXiv · 1208.4840

Directly Measuring the Tensor Structure of the Scalar Coupling to Gauge Bosons

Daniel Stolarski·Roberto Vega-Morales
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Abstract

Kinematic distributions in the decays of the newly discovered resonance to four leptons can provide a direct measurement of the tensor structure of the particle's couplings to gauge bosons. Even if the particle is shown to be a parity even scalar, measuring this tensor structure is a necessary step in determining if this particle is responsible for giving mass to the Z. We consider a Standard Model like coupling as well as coupling via a dimension five operator to either ZZ or Zγ. We show that using full kinematic information from each event allows discrimination between renormalizable and higher dimensional coupling to ZZ at the 95% confidence level with O(50) signal events, and coupling to Zγcan be distinguished with as few as 20 signal events. This shows that these measurements can be useful even with this year's LHC data.

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Daniel Stolarski, Roberto Vega-Morales. 2012-09-05. Directly Measuring the Tensor Structure of the Scalar Coupling to Gauge Bosons. https://doi.org/10.1103/physrevd.86.117504

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