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A data sample corresponding to 1.23 million hadronic Z decays collected by the ALEPH detector at LEP has been searched for signals of the production of a non-minimal CP-even Higgs boson h in the reaction e + e ! hZ. The h decay modes considered were: those of the minimal standard model Higgs boson, with modied branching ratios; decays into a pair of CP-odd Higgs bosons A; and decays into invisible nal states. Only one event was found, a very acoplanar e + e pair which could originate from the standard model background process e + e ! e + e. Upper limits for the cross-section of the reaction e + e ! hZ have been derived as a function of m h , the mass of the Higgs boson h. In the case of invisible decays, the 95% CL lower limit on m h is 65 GeV/c 2 for a production cross-section equal to that of a minimal standard model Higgs boson. When combined with previous ALEPH results on the reaction e + e ! hA, these cross-section upper limits exclude a domain in the (m h , m A) plane of the MSSM such that, if invisible h and A decays can be neglected, 95% CL lower limits of 44 and 21 GeV/c 2 result for m h and m A , respectively, independent of the other parameters of the model.

The lifetime of the Bs0 has been measured in a data sample of 8890000 hadronic events recorded with the ALEPH detector at LEP. After background subtraction 30.8 +/- 6.9 events are attributed to the semileptonic decay of the Bs0 to a Ds- and an opposite-sign lepton. A maximum-likelihood fit to the distribution of the proper times of these events yields a Bs0 lifetime of τBs = 1.92-0.35+0.45 +/- 0.04 ps

The strong coupling constant is determined from the leptonic branching ratios, the lifetime, and the invariant mass distribution of the hadronic final state of the τ lepton, using data accumulated at LEP with the ALEPH detector. The strong coupling constant measurement, αs(mτ2) = 0.330+/-0.046, evolved to the Z mass yields αs(MZ2) = 0.188+/-0.005. The error includes experimental and theoretical uncertainties, the latter evaluated in the framework of the Shifman, Vainshtein and Zakharov (SVZ) approach. The method allows the non-perturbative contribution to the hadronic decay rate to be determined to be 0.3+/-0.5%

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