MASS LIMITS OF INVISIBLY DECAYING HIGGS PARTICLES FROM THE CERN LEP DATA

In the Majoron models the SU(2) Higgs doublet can decay invisibly into a Majoron pair via its mixing with a singlet. An analysis of the CERN LEP data shows the invisible decay mode to be more visible than the SM decay. For these models, the dominantly doublet Higgs field H is shown to have a mass limit within +/-6 GeV of the SM limit irrespective of the model parameters. But the dominantly singlet one S can be arbitrarily light for a sufficiently small mixing angle.