The four LEP collaborations, ALEPH, DELPHI, L3 and OPAL, have searched for the neutral Higgs bosons which are predicted by the Minimal Supersymmetric Standard Model (MSSM). The data of the four collaborations are statistically combined and examined for their consistency with the background hypothesis and with a possible Higgs boson signal. The combined LEP data show no significant excess of events which would indicate the production of Higgs bosons. The search results are used to set upper bounds on the cross-sections of various Higgs-like event topologies. The results are interpreted within the MSSM in a number of "benchmark" models, including CP-conserving and CP-violating scenarios. These interpretations lead in all cases to large exclusions in the MSSM parameter space. Absolute limits are set on the parameter tan β and, in some scenarios, on the masses of neutral Higgs bosons.

A search for neutral Higgs bosons has been performed using the full sample of Z 0 decays collected by the OPAL detector at LEP up to 1995. The data were taken at centre-of-mass energies between 88 GeV and 95 GeV and correspond to an integrated luminosity of approximately 160 pb 1. The present search addresses the processes Z 0 !H 0 Z and h 0 Z , where H 0 is the Higgs boson predicted by the Standard Model and h 0 the lightest neutral scalar Higgs boson predicted in the framework of the Minimal Supersymmetric Standard Model. For the virtual Z 0 boson, Z , the following decay c hannels are considered: Z ! , e + e and +. One candidate event

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The Sudbury Neutrino Observatory (SNO) has precisely determined the total active (ν x ) 8 B solar neutrino flux without assumptions about the energy dependence of the ν e survival probability. The measurements were made with dissolved NaCl in the heavy water to enhance the sensitivity and signature for neutral-current interactions. The flux is found to be 5.21 ± 0.27 (stat) ± 0.38 (syst) × 10 6 cm −2 s −1 , in agreement with previous measurements and standard solar models. A global analysis of these and other solar and reactor neutrino results yields ∆m 2 = 7.1 +1.2 −0.6 × 10 −5 eV 2 and θ = 32.5 +2. ES).Only electron neutrinos produce charged-current interactions (CC), while the neutral-current (NC) and elastic scattering (ES) reactions have sensitivity to non-electron flavors. The NC reaction measures the total flux of all active neutrino flavors above a threshold of 2.2 MeV. SNO previously measured the NC rate by observing neutron captures on deuterons, and found that a Standard-Model description with an undistorted 8 B neutrino spectrum and CC, ES, and NC rates due solely to ν e interactions was rejected [2, 3]. This Letter presents measurements of the CC, NC, and ES rates from SNO's dissolved salt phase.The addition of 2 tonnes of NaCl to the kilotonne of heavy water increased the neutron capture efficiency and the associated Cherenkov light. The solution was thoroughly mixed and