New result from ALEPH in e+e- annihilations at √s = 161-172 GeV

After the energy upgrade of CERN's LEP electron-positron collider, an integrated luminosity of 22 pb-1 has been collected by the ALEPH experiment during the 1996 data taking period, with a centre-of-mass energy of 161 and 172 GeV. With this data, new studies of the standard electroweak theory and of quantum chromodynamics observables are presented and most notably, precision measurements of mW are obtained from the first observation of W pair decays. No evidence of Higgs boson production, nor any signal of supersymmetry or other new physics has been found in the data so that limits are derived, in the framework of the SM and of its minimal supersymmetric extension. The anomalous four jet production excess that was reported at lower centre-of-mass energies of 130-136 GeV is partially confirmed with the new data, though the origin of such excess in not yet well understood and necessitates further studies. All the presented ALEPH results are preliminary and subject to modifications. (author)