Abstract
We study the LHC discovery potential in the search for heavy neutral leptons (HNL) with a new signature: a displaced shower in the CMS muon detector, giving rise to a large cluster of hits forming a displaced shower. A new Delphes module is used to model the CMS detector response for such displaced decays. We reinterpret a dedicated CMS search for neutral long-lived particles decaying in the CMS muon endcap detectors for the minimal HNL scenario. We demonstrate that this new strategy is particularly sensitive to active-sterile mixings with τ leptons, due to hadronic τ decays. HNL masses between ~ 1–6 GeV can be accessed for mixings as low as |VτN|2~10−7, probing unique regions of parameter space in the τ sector.
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Cottin, G., Helo, J.C., Hirsch, M. et al. Long-lived heavy neutral leptons with a displaced shower signature at CMS. J. High Energ. Phys. 2023, 11 (2023). https://doi.org/10.1007/JHEP02(2023)011
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DOI: https://doi.org/10.1007/JHEP02(2023)011