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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Theνe − e − elastic scattering cross-section was measured with a CsI(Tl) scintillating crystal array having a total mass of 187 kg. The detector was exposed to an average reactorνe flux of 6.4 × 10 12 cm −2 s −1 at the Kuo-Sheng Nuclear Power Station. The experimental design, conceptual merits, detector hardware, data analysis and background understanding of the experiment are presented. Using 29882/7369 kg-days of Reactor ON/OFF data, the Standard Model (SM) electroweak interaction was probed at the squared 4-momentum transfer range of Q 2 ∼ 3 × 10 −6 GeV 2 . The ratio of experimental to SM cross-sections of ξ = [1.08 ± 0.21(stat) ± 0.16(sys)] was measured. Constraints on the electroweak parameters (gV , gA) were placed, corresponding to a weak mixing angle measurement of sin 2 θW = 0.251 ± 0.031(stat ) ± 0.024(sys ). Destructive interference in the SMνe−e process was verified. Bounds on anomalous neutrino electromagnetic properties were placed: neutrino magnetic moment at µν e < 2.2 × 10 −10 µB and the neutrino charge radius at −2.1 × 10 −32 cm 2 < r 2 νe < 3.3 × 10 −32 cm 2 , both at 90% confidence level.

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