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arXiv · 1507.03098

A scalar hint from the diboson excess?

Giacomo Cacciapaglia·Aldo Deandrea·Michio Hashimoto
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Abstract

In view of the recent diboson resonant excesses reported by both ATLAS and CMS Collaborations, we suggest that a new weak singlet pseudo-scalar particle, $\eta_W$, may decay into two weak bosons while being produced in gluon fusion at the LHC. The couplings to the gauge bosons can arise from a Wess-Zumino-Witten anomaly term and thus we study an effective model based on the anomaly term as a well motivated phenomenological model. In models where the pseudo-scalar arises as a composite state, the coefficients of the anomalous couplings can be related to the fermion components of the underlying dynamics. We provide an example to test the feasibility of the idea.

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Giacomo Cacciapaglia, Aldo Deandrea, Michio Hashimoto. 2015-07-11. A scalar hint from the diboson excess?. https://doi.org/10.1103/physrevlett.115.171802

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