[en] Some predictions on lifetimes, according to the spectator model, for the weak decay of heavy mesons are presented. (L.C.)

[en] This paper reports the search of staus, the supersymmetry partner of the tau, using the data taken by DELPHI/LEP in 1995, at 130 GeV and 136 GeV, and in 1996, at 161 GeV and 172 GeV, above WW production threshold. The integrated luminosities were 2.9 pb^-1, for 130 GeV, 3.0 pb^-1 for 136 GeV, 9.6 pb^-1 for 161 GeV and 10.2 pb^-1 for 172 GeV. (author)

[en] Short communication

[en] The status of the study of the rare decay B_d⁰ → K^*0μ⁺μ^-, with K^*0 → K⁺π^-, or its charged conjugate state, using the LHCb detector is presented. This decay is very sensitive to deviations from Standard Model physics through Forward- Backward and CP asymmetries, among other observables. In one year of LHCb data taking we expect to collect about 4400 of these events with a B/S ratio below 4. This allows the determination of the branching ratio and of the possible CP asymmetry of the branching ratio with a precision of a few percent. The evaluation of the sensitivity of the other observables needs a better understanding of the backgrounds and their distributions. Therefore, more statistics of background simulations is needed. However, I find good resolutions for the measurement of the relevant quantities. (author)

[en] We study the contribution of residual S-P interaction to ordinary muon decay, μ→eγ transitions, and the K₀-K-bar₀ system. With the hypothesis of right-handed neutrino singlets, we discuss radiative neutrino decay

[en] Data taken by the DELPHI experiment at centre-of-mass energy of 183 GeV has been used to search for the supersymmetric partners of tau leptons. The observations are in agreement with standard model predictions. These results were subsequently combined with those obtained by DELPHI during the 1995 and 1996 LEP runs and are interpreted in terms of exclusion regions in the (M_τ-bar, M_χ-bar₁⁰) planes. (author)

[en] Short communication

[en] Short communication

[en] Full text follows: We included detector inefficiencies, dead time, noise and cross talk effects in the digitization module of SICB, the simulation program for the LHCb detector, and studied its influence in the performance of the level zero muon trigger algorithm. For reasonable values for the parameters characterizing these effects, obtained in beam tests of prototypes, the degradation of the trigger performance is small and it fulfills our requirements for minimum bias retention and signal efficiency. An object oriented design for the digitization was also developed and implemented as a first step on the software migration to C++. (author)

[en] We present a composite scenario based on the SU_L(2)direct-product U(1)_Y direct-product SU_L^*(2) group. New interactions are predicted at the usual electroweak scale. New heavy fermions can be produced in a renormalizable model. A new type of light excited neutrinos can occur and are shown to be naturally consistent with the recent results from the CERN e⁺e- collider LEP on the Z width