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We calculate the prediction for the anomalous weak-magnetic form factor of the tau lepton at q 2 = M 2 Z within the Standard Model. With all particles on-shell, this is a electroweak gauge invariant quantity. Its value is a w τ (M 2 Z ) = − (2.10 + 0.61 i) × 10 −6 . We show that the transverse and normal components of the single-tau polarization of tau pairs produced at e + e − unpolarized collisions are sensitive to the real and absorptive parts of the anomalous weak-magnetic dipole moment of the tau. The sensitivity one can achieve at LEP in the measurement of this dipole moment is discussed.

The cross section for prompt antiproton production in collisions of protons with an energy of 6.5 TeV incident on helium nuclei at rest is measured with the LHCb experiment from a data set corresponding to an integrated luminosity of 0.5 nb −1. The target is provided by injecting helium gas into the LHC beam line at the LHCb interaction point. The reported results, covering antiproton momenta between 12 and 110 GeV=c, represent the first direct determination of the antiproton production cross section in p-He collisions, and impact the interpretation of recent results on antiproton cosmic rays from space-borne experiments.

Using LEP1, SLD and LEP2 data, for tau lepton production, and data from pp colliders and LEP2, for W decays into tau leptons, we set model independent limits on non-standard electromagnetic and weak magnetic moments of the tau lepton. The most general effective Lagrangian giving rise to tau moments is used without further assumptions. Precise bounds (2σ) on the non-standard model contributions to tau electromagnetic (−0.007 < a γ < 0.005), tau Z-magnetic (−0.0024 < a Z < 0.0025) and tau W-magnetic (−0.003 < κ W < 0.004) dipole moments are set from the analysis.