Formula omitted] symmetry in two-doublet models, U bosons or light scalars, and ψ and ϒ decays

Abstract

ψ and ϒ decays may be used to search for light neutral spin-1 or spin-0 bosons associated with a broken extra-U(1) symmetry, local or global, acting axially on quarks and leptons, as may be present in supersymmetric theories with a λH1H2S superpotential. Recent data on ϒ→γ+invisible neutral constrain an axial, pseudoscalar or scalar coupling to b to fbA<4×10−7mU (MeV)/Binv, fbP<4×10−3/Binv or fbS<6×10−3/Binv, respectively. This also constrains, from universality properties, couplings to electrons to feA<4×10−7mU (MeV)/Binv, feP<4×10−7/Binv or feS<6×10−7/Binv.The pseudoscalar a (possibly traded for a light gauge boson, or scalar particle) should then be, for invisible decays of the new boson, for >96% singlet and <4% doublet, for tanβ>1. Or, more generally, <4%/(tan2βBinv) doublet, which implies a very small rate for the corresponding ψ decay, B(ψ→γ+neutral)Binv≲10−6/tan4β. Similar results are obtained for new spin-1 or spin-0 neutral bosons decaying into μ+μ−.