Search for heavy neutral leptons in B-meson decays

Journal article

A search for long-lived heavy neutral leptons produced in B-meson decays and decaying to a μ±π∓ final state is performed with data collected by the LHCb experiment in proton-proton collisions at a centre-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 5 fb−1. The results are interpreted in both lepton-number-conserving and lepton-number-violating scenarios. No significant excess is observed. Constraints are placed on the squared mixing element |UμN|2 to the active muon neutrino, under the assumption that couplings to other lepton flavours are negligible, in the mass range of 1.6–5.5 GeV.

Authors: Aaij, R; Abdelmotteleb, ASW; Abellan Beteta, C; Abudinén, F; Ackernley, T

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: Springer
• Journal: Journal of High Energy Physics
• Volume: 2026
• Issue: 3
• Article number: 178
• Publication date: 2026-03-18
• Acceptance date: 2026-01-18
• DOI: 10.1007/jhep03(2026)178
• EISSN: 1029-8479
• ISSN: 1126-6708
• Language: English
• Keywords: Hadron-Hadron Scattering; Exotics; Beyond Standard Model