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arXiv · 1803.00842

Searching for scalar boson decaying into light $Z'$ boson at collider experiments in $U(1)_{L_μ-L_τ}$ model

Abstract

We study a model with $U(1)_{L_μ- L_τ}$ gauge symmetry and discuss collider searches for a scalar boson, which breaks $U(1)_{L_μ- L_τ}$ symmetry spontaneously, decaying into light $Z'$ gauge boson. In this model, the new gauge boson, $Z'$, with a mass lighter than $\mathcal{O}(100)$ MeV, plays a role in explaining the anomalous magnetic moment of muon via one-loop contribution. For the gauge boson to have such a low mass, the scalar boson, $ϕ$ with $\mathcal{O}(100)$ GeV mass appears associated with the symmetry breaking. We investigate experimental constraints on $U(1)_{L_μ- L_τ}$ gauge coupling, kinetic mixing, and mixing between the SM Higgs and $ϕ$. Then collider search is discussed considering $ϕ$ production followed by decay process $ϕ\to Z' Z'$ at the large hadron collider and the international linear collider. We also estimate discovery significance at the linear collider taking into account relevant kinematical cut effects.

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Takaaki Nomura, Takashi Shimomura. 2019-07-19. Searching for scalar boson decaying into light $Z'$ boson at collider experiments in $U(1)_{L_μ-L_τ}$ model. https://doi.org/10.1140/epjc%2Fs10052-019-7094-8

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