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arXiv · 2004.14515

LSND Constraints on the Higgs Portal

Saeid Foroughi-Abari·Adam Ritz
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Abstract

High-luminosity fixed target experiments provide impressive sensitivity to new light weakly coupled degrees of freedom. We revisit the minimal case of a scalar singlet $S$ coupled to the Standard Model through the Higgs portal, that decays visibly to leptons for scalar masses below the di-pion threshold. The dataset from the LSND experiment is found to impose the leading constraints within two mass windows between $m_S \sim 100$ and 350 MeV. In the process, we analyze a number of scalar production channels in the target, finding that proton bremsstrahlung provides the dominant channel at LSND beam energies.

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Saeid Foroughi-Abari, Adam Ritz. 2020-04-29. LSND Constraints on the Higgs Portal. https://doi.org/10.1103/physrevd.102.035015

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