Search for Heavy Isosinglet Neutrinos in e${}^{+}$e${}^{-}$ Annihilation at 130$<\sqrt{s}<$189 GeV

L3 Collaboration

A search for heavy neutrinos that are isosinglets under the standard $SU(2{)}_L$ gauge group is made at center-of-mass energies 130 $<\sqrt{s}<$ 189 GeV with the L3 detector at LEP…