LSND constraints on the Higgs portal
Saeid Foroughi-Abari, Adam Ritz
Abstract
High-luminosity fixed target experiments provide impressive sensitivity to new light weakly coupled degrees of freedom. We revisit the minimal case of a scalar singlet $S$ coupled to the Standard Model through the Higgs portal that decays visibly to leptons for scalar masses below the dipion threshold. The dataset from the LSND experiment is found to impose the leading constraints within two mass windows between ${m}_{S}\ensuremath{\sim}100$ and 350 MeV. In the process, we analyze a number of scalar production channels in the target, finding that proton bremsstrahlung provides the dominant channel at LSND beam energies.
Topics & Concepts
Particle physicsPhysicsScalar (mathematics)Higgs bosonLeptonBremsstrahlungSensitivity (control systems)Nuclear physicsMathematicsGeometryEngineeringElectronElectronic engineeringParticle physics theoretical and experimental studiesDark Matter and Cosmic PhenomenaNeutrino Physics Research