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arXiv · 2007.03708

Soft displaced leptons at the LHC

Freya Blekman·Nishita Desai·Anastasiia Filimonova·Abanti Ranadhir Sahasransu·Susanne Westhoff
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Abstract

Soft displaced leptons are representative collider signatures of compressed dark sectors with feeble couplings to the standard model. Prime targets are dark matter scenarios where co-scattering or co-annihilation sets the relic abundance upon freeze-out. At the LHC, searches for soft displaced leptons are challenged by a large background from hadron or tau lepton decays. In this article, we present an analysis tailored for displaced leptons with a low transverse momentum threshold at 20 GeV. Using a neural network, we perform a comprehensive analysis of the event kinematics, including a study of the expected detection efficiencies and backgrounds at small momenta. Our results show that weak-scale particles decaying into soft leptons with decay lengths between 1mm and 1m can be probed with LHC Run 2 data. This motivates the need for dedicated triggers that maximize the sensitivity to displaced soft leptons.

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Freya Blekman, Nishita Desai, Anastasiia Filimonova, Abanti Ranadhir Sahasransu, Susanne Westhoff. 2020-07-07. Soft displaced leptons at the LHC. https://doi.org/10.1007/jhep11(2020)112

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