Searching for lepton number violating $\Lambda$ baryon decays mediated by GeV-scale Majorana neutrino with LHCb

Abstract

We consider the lepton-number-violating processes in ${\Lambda }_b$/${\Lambda }_c$ decays mediated by on-shell GeV-scale sterile neutrino. We calculate the branching ratio for the following processes: ${\Lambda }_b^0\to {\mathcal{B}}^{+}{\mu }^{-}{\mu }^{-}{\pi }^{+}$, where ${\mathcal{B}}^{+}$ is ${\Lambda }_c^{+}$ or proton, and ${\Lambda }_c^{+}\to \Lambda {\mu }^{+}{\mu }^{+}{\pi }^{-}$, as function of the mass of the sterile neutrino $m_N$ and the heavy-light mixing coefficient of the extended Pontecorvo-Maki-Nakagawa-Sakata (PMNS) matrix $|U_{\mu N}{|}^2$. The effect of finite detector size is included in our calculation. After comparing the theoretical effective branching ratio with the expected experimental ability of LHCb, we give the sensitivity upper bounds on $|U_{\mu N}{|}^2$ on the ($|U_{\mu N}{|}^2$-$m_N$) plane. These channels give comparable results with the bounds given by different search strategies (e.g., at Belle, NuTeV, DELPHI and BEBC) in the mass region $m_N\simeq$ 0.25 GeV - 4.5 GeV, and the limits are stronger in the mass range 2 GeV $<m_N<$ 4.5 GeV.

arXiv comment10 pages, 4 figures

References in corpus (46)

• A Unified Approach to the Classical Statistical Analysis of Small Signals
• Sterile Neutrinos as Dark Matter
• LHCb Detector Performance
• The $\nu$MSM, Dark Matter and Baryon Asymmetry of the Universe
• The Search for Heavy Majorana Neutrinos
• A New Dark Matter Candidate: Non-thermal Sterile Neutrinos
• Neutrinoless Double-Beta Decay: Status and Prospects
• Status and Future of Nuclear Matrix Elements for Neutrinoless Double-Beta Decay: A Review
• Neutrinoless double beta decay: 2015 review
• Dark Matter, Baryogenesis and Neutrino Oscillations from Right Handed Neutrinos
• Sterile Neutrinos as the Origin of Dark and Baryonic Matter
• ${\Lambda }_b\to p{\ell }^{-}{\bar{\nu }}_{\ell }$ and ${\Lambda }_b\to {\Lambda }_c{\ell }^{-}{\bar{\nu }}_{\ell }$ form factors from lattice QCD with relativistic heavy quarks
• Measurements of prompt charm production cross-sections in $pp$ collisions at $\sqrt{s}=13\mathrm{TeV}$
• Search for Neutral Heavy Leptons in a High-Energy Neutrino Beam
• ${\Lambda }_b\to \Lambda {\ell }^{+}{\ell }^{-}$ form factors, differential branching fraction, and angular observables from lattice QCD with relativistic $b$ quarks
• Search for heavy neutrinos at Belle
• Sterile neutrinos in lepton number and lepton flavor violating decays
• Measurement of b-hadron fractions in 13 TeV pp collisions
• Majorana Neutrinos and Same-Sign Dilepton Production at LHC and in Rare Meson Decays
• Measurement of the $b$-quark production cross-section in 7 and 13 TeV $pp$ collisions
• Probing Majorana neutrinos in rare K and D, D_s, B, B_c meson decays
• Implications of Improved Upper Bounds on $|\Delta L|=2$ Processes
• Upper Bounds on Lepton-number Violating Processes
• ${\Lambda }_c\to \Lambda {\ell }^{+}{\nu }_{\ell }$ form factors and decay rates from lattice QCD with physical quark masses
• K-meson neutrinoless double muon decay as a probe of neutrino masses and mixings
• Sensitivity of Lepton Number Violating Meson Decays in Different Experiments
• On Lepton Flavor Violation in Tau Decays
• Sterile neutrinos in tau lepton decays
• Lepton number violation in top quark and neutral B meson decays
• ${\Lambda }_c^{\pm }$ production in pp collisions with a new fragmentation function
• Sensitivity to Majorana neutrinos in $\Delta L=2$ decays of $B_c$ meson at LHCb
• CP violation in lepton number violating semihadronic decays of $K,D,D_s,B,B_c$
• Measurement of the $B^{\pm }$ production cross-section in pp collisions at $\sqrt{s}=$ 7 and 13 TeV
• Remarks on the lifetime of sterile neutrinos and the effect on detection of rare meson decays M+ -> M'- lepton+ lepton+
• Lepton number violating four-body tau lepton decays
• Rare decays of B mesons via on-shell sterile neutrinos
• Lepton number violation by heavy Majorana neutrino in $B$ decays
• Hadronic structure aspects of $K^{+}\to {\pi }^{-}+l_1^{+}+l_2^{+}$ decays
• Sensitivity limits on heavy-light mixing $|U_{\mu N}{|}^2$ from lepton number violating $B$ meson decays
• Double beta decay of sigma^- hyperons
• Sensitivity bounds on heavy neutrino mixing $|U_{\mu N}{|}^2$ and $|U_{\tau N}{|}^2$ from LHCb upgrade
• Lepton number violation in $B_s$ meson decays induced by an on-shell Majorana neutrino
• Search for lepton-number-violating signals in the charm sector
• Exploring GeV-scale Majorana neutrinos in lepton-number-violating ${\Lambda }_b^0$ baryon decays
• $\Delta L=2$ hyperon semileptonic decays
• Matrix elements of four-quark operators and ΔL=2 hyperon decays

Cited by in corpus (8)

• Heavy Flavour Physics and CP Violation at LHCb: a Ten-Year Review
• Light sterile neutrinos and lepton-number-violating kaon decays in effective field theory
• CP violation with GeV-scale Majorana neutrino in ${\Lambda }_b\to ({\Lambda }_c^{+},p^{+}){\pi }^{+}{\mu }^{-}{\mu }^{-}$ decays
• $\Delta$L=2 hyperon decays induced by Majorana neutrinos and doubly-charged scalars
• Resonant Majorana neutrino effects in $\Delta$L=2 four-body hyperon decays
• Sterile neutrinos in ${\Lambda }_b^0\to ({\Lambda }_c^{+},p^{+}){\ell }_1^{-}{\ell }_2^{-}{\ell }_3^{+}\nu$ decays
• Dirac-Majorana neutrinos distinction in four-body decays
• CP violation in $B_s$ decays mediated by two nearly-degenerate Majorana neutrinos