Search for long-lived particles decaying to $e^{\pm }{\mu }^{\mp }\nu$

Abstract

Long-lived particles decaying to $e^{\pm }{\mu }^{\mp }\nu$, with masses between 7 and $50$ GeV/c${}^2$ and lifetimes between 2 and $50$ ps, are searched for by looking at displaced vertices containing electrons and muons of opposite charges. The search is performed using $5.4$ fb${}^{-1}$ of $pp$ collisions collected with the LHCb detector at a centre-of-mass energy of $\sqrt{s}=13$ TeV. Three mechanisms of production of long-lived particles are considered: the direct pair production from quark interactions, the pair production from the decay of a Standard-Model-like Higgs boson with a mass of $125$ GeV/c${}^2$, and the charged current production from an on-shell $W$ boson with an additional lepton. No evidence of these long-lived states is obtained and upper limits on the production cross-section times branching fraction are set on the different production modes.

All figures and tables, along with any supplementary material and additional information, are available at https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2020-027.html (LHCb public pages)

References in corpus (28)

• PYTHIA 6.4 Physics and Manual
• PYTHIA 6.2 Physics and Manual
• The automated computation of tree-level and next-to-leading order differential cross sections, and their matching to parton shower simulations
• A Brief Introduction to PYTHIA 8.1
• New Generation of Parton Distributions with Uncertainties from Global QCD Analysis
• A Supersymmetry Primer
• PDF4LHC recommendations for LHC Run II
• UFO - The Universal FeynRules Output
• LHCb Detector Performance
• Automatic spin-entangled decays of heavy resonances in Monte Carlo simulations
• Search for $A^{\prime }\to {\mu }^{+}{\mu }^{-}$ decays
• Precision luminosity measurements at LHCb
• Search for hidden-sector bosons in $B^0\to K^{\ast 0}{\mu }^{+}{\mu }^{-}$ decays
• Search for heavy neutral leptons in decays of $W$ bosons produced in 13 TeV $pp$ collisions using prompt and displaced signatures with the ATLAS detector
• Search for Majorana neutrinos in $B^{-}\to {\pi }^{+}{\mu }^{-}{\mu }^{-}$ decays
• Collider Searches for Long-Lived Particles Beyond the Standard Model
• Search for long-lived particles that decay into final states containing two electrons or two muons in proton-proton collisions at sqrt(s) = 8 TeV
• Search for long-lived, weakly interacting particles that decay to displaced hadronic jets in proton-proton collisions at $\sqrt{s}=8$ TeV with the ATLAS detector
• Search for pair-produced long-lived neutral particles decaying in the ATLAS hadronic calorimeter in $pp$ collisions at $\sqrt{s}$ = 8 TeV
• Reweighting with Boosted Decision Trees
• Interpolation between multi-dimensional histograms using a new non-linear moment morphing method
• Search for massive long-lived particles decaying semileptonically in the LHCb detector
• Updated search for long-lived particles decaying to jet pairs
• A Measurement of Rb using a Vertex Mass Tag
• Search for long-lived particles in final states with displaced dimuon vertices in $pp$ collisions at $\sqrt{s}=$ 13 TeV with the ATLAS detector
• Search for Higgs-like bosons decaying into long-lived exotic particles
• Search for displaced vertices of oppositely charged leptons from decays of long-lived particles in $pp$ collisions at $\sqrt{s}$ = 13 TeV with the ATLAS detector
• Measurement of the $B^0\to K^{\ast 0}{e}^{+}{e}^{-}$ branching fraction at low dilepton mass

Cited by in corpus (10)

• Primordial black holes from an electroweak phase transition
• Implications of Feebly Interacting Dark Sector on Neutron Star Properties and Constraints from GW170817
• Unleashing the full power of LHCb to probe Stealth New Physics
• Search for long-lived particles decaying to leptons with large impact parameter in proton-proton collisions at $\sqrt{s}$ = 13 TeV
• Heavy Neutrinos at the FCC-hh in the $U(1{)}_{B-L}$ Model
• Search for long-lived heavy neutral leptons decaying in the CMS muon detectors in proton-proton collisions at $\sqrt{s}$ = 13 TeV
• Energetic long-lived particles in the CMS muon chambers
• Long-Lived Light Mediators from Higgs boson Decay at HL-LHC, FCC-hh and a Proposal of Dedicated LLP Detectors for FCC-hh
• Testing the seesaw mechanisms via displaced right-handed neutrinos from a light scalar at the HL-LHC
• Long-lived Light Mediators in a Higgs Portal Model at the FCC-ee