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.

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An event sample enriched in semileptonic decays of b hadrons is selected using an inclusive lepton selection from approximately 3.0 million hadronic Z 0 decays collected with the OPAL detector. This sample is used to investigate B meson oscillations by reconstructing a proper decay time for the parent of each lepton, using a jet charge method to estimate the production flavour of this parent, and using the lepton charge to tag the decay flavour. We measure the mass difference between the two B 0 d mass eigenstatesFor the B 0 s system, we find ∆m s > 3.1 ps −1 at the 95% confidence level. This limit varies only a little if alternative limit setting approaches are adopted. Regions at higher ∆m s values are also excluded with some methods for setting the limit.By studying the charge symmetry of the B 0 d mixing structure, we are able to constrain possible CP and CPT violating effects. We measure the CP violation parameter Re ǫ B = −0.006 ± 0.010 ± 0.006 and the indirect CPT violating parameter Im δ B = −0.020 ± 0.016 ± 0.006 . If we invoke CPT symmetry, then we obtainRe ǫ B = 0.002 ± 0.007 ± 0.003 .

A narrow resonance in D * − p and D * +p invariant mass combinations is observed in inelastic electron-proton collisions at centre-of-mass energies of 300 GeV and 320 GeV at HERA. The resonance has a mass of 3099 ± 3 (stat.) ± 5 (syst.) MeV and a measured Gaussian width of 12 ± 3 (stat.) MeV, compatible with the experimental resolution. The resonance is interpreted as an anti-charmed baryon with a minimal constituent quark composition of uuddc, together with the charge conjugate.To be submitted to Phys.