Enhancing the Sensitivity to Seesaw Predictions in Gauged $B-L$ Scenarios

Abstract

New gauge bosons coupled to heavy neutral leptons (HNLs) are simple and well-motivated extensions of the Standard Model. In searches for HNLs in proton fixed-target experiments, we find that a large population of gauge bosons ($Z^{\prime }$) produced by proton bremsstrahlung may decay to HNLs, leading to a significant improvement in existing bounds on the ($m_{HNL},U_{\alpha }$), where $U_{\alpha }$ represent the mixing between HNL and the active neutrinos with flavor $\alpha$. We study this possibility in fixed target experiments with the 8 GeV proton beams, including SBND, MicroBooNE, and ICARUS, as well as DUNE and DarkQuest at 120 GeV. We find the projected sensitivities to additional $Z^{\prime }$-mediated HNL production can bring the seesaw mechanism of the neutrino masses within a broadened experimental reach.

Accepted and Published in PRD. 12 pages, 8 Figures

References in corpus (15)

• Search for heavy neutrinos in $K^{+}\to {\mu }^{+}{\nu }_H$ decays
• Search for heavy neutral lepton production in $K^{+}$ decays to positrons
• GeV-scale neutrinos: interactions with mesons and DUNE sensitivity
• Blast from the past II: Constraints on heavy neutral leptons from the BEBC WA66 beam dump experiment
• Dark Scalars and Heavy Neutral Leptons at DarkQuest
• Dark Matter and Neutrino Mass from the Smallest Non-Abelian Chiral Dark Sector
• Dark Sector Production via Proton Bremsstrahlung
• New production channels for light dark matter in hadronic showers
• The MicroBooNE Experiment, the NuMI Absorber, and Heavy Neutral Leptons
• BSM Targets at a "Target-less DUNE"
• Scintillation Light in SBND: Simulation, Reconstruction, and Expected Performance of the Photon Detection System
• Dark photon production via elastic proton bremsstrahlung with non-zero momentum transfer
• Extending the Reach of Leptophilic Boson Searches at DUNE and MiniBooNE with Bremsstrahlung and Resonant Production
• Light $Z^{\prime }$ and Dirac fermion dark matter in the $B-L$ model
• Pauli form factor contributions to the inelastic proton bremsstrahlung and dark photon production

Cited by in corpus (2)

• From oversimplified to overlooked: the case for exploring Rich Dark Sectors
• Finding BSM Needles in Electromagnetic Haystacks at DUNE