English

Soft displaced leptons at the LHC

High Energy Physics - Phenomenology 2020-11-24 v2 High Energy Physics - Experiment

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.

Keywords

Cite

@article{arxiv.2007.03708,
  title  = {Soft displaced leptons at the LHC},
  author = {Freya Blekman and Nishita Desai and Anastasiia Filimonova and Abanti Ranadhir Sahasransu and Susanne Westhoff},
  journal= {arXiv preprint arXiv:2007.03708},
  year   = {2020}
}

Comments

25 pages, 9 figures, 5 tables

R2 v1 2026-06-23T16:55:51.734Z