[en] Interactions between the products of the hadronic decays of different Ws in WW pair events can occur at several stages: from the colour rearrangement between the quarks coming from the primary branching, to the gluon exchange during the the parton cascade, to the mixing of identical pions due to Bose-Einstein correlations. Besides the intrinsic interest of their study related to the understanding of the multiparticle production mechanisms, these phenomena can affect the ultimate accuracy in the W mass measurement by LEP 2. The status of the experimental analysis on interconnection effects between W pairs decaying hadronically is reviewed in this paper. For what is related to Bose-Einstein interference, only the results from ALEPH and DELPHI are presented, being L3 and OPAL discussed in another contribution to this conference

[en] The interaction of high energy photons (or electrons) with matter gives rise to the phenomenon of multiplicative showers, used in the detectors called electromagnetic calorimeters to measure through complete absorption the energy of an incident particle. Cherenkov electromagnetic calorimeters measure the incident energy by means of the yield of Cherenkov light from the charged secondary particles in the shower. These detectors, widely used in high energy physics, provide in modern apparata a precise measurement of energy and position of the photons or electrons produced in the interaction. A detailed simulation of the development of electromagnetic showers and of the Cherenkov light propagation predicts an increase of the signal for lead-glass Cherenkov calorimeters in the presence of strong external magnetic fields. This increase is related to the Faraday effect on Cherenkov light, and can become sizeable in experimental conditions such as the typical ones in high energy physics

[en] The study of the factorial moments of the rapidity distribution and of the (y, φ) distribution for hadrons produced in the decay of the Z⁰, by means of the DELPHI detector at LEP, has shown no deviations from the predictions of Parton-Shower models. Intermittent behavior observed in the latter case has been found to be compatible with jet cascading mechanism

[en] The incorporation of low-and medium-level wastes in cement can give rise to serious problems due to the interaction between radwastes and cement components. Some troubles can occur during the first stages of the cementation process while deleterious phenomena come into evidence in the medium-and long-term. With the aim to improve the quality of the final waste forms a pretreatment of the waste streams is often necessary, as well as the addition of some special agents to the cement matrix. The prediction of the long-term behaviour of the final products is of main importance in this research field. To this purpose some accelerated tests have been proposed, but many effort would be further devoted to the comprehension of the waste/matrix interaction. In this paper the principal waste streams are reviewed together with the possible remedies which seem to be more suitable for their cementation. Thus the opportunity of separatly handling and solidifying different types of waste is once more supported

[en] The techniques used for classifying the decays of the Z⁰ into different quark flavours are reviewed. The results presented by the LEP collaborations on the hadronic branching fractions of the Z⁰ are summarized. ((orig.))

[en] The drift of a bunch of charged particles has been simulated in a scenario based on the set-up for the proposed experiment on the gravitational acceleration of antimatter. The effect of the mutual electrostatic repulsion of the particles and of the external magnetic field on the Time Of Flight distribution has been studied

[en] Simulations of electromagnetic calorimeters based on the parametrization of the shower shape are used more and more to save computer time in Monte Carlo programs for high energy physics. In this paper we present a Monte Carlo study, based on the EGS4 code, of the fluctuations and the correlations in the energy deposited by photon-initiated showers. We report on an investigation we made on the use of the uncertainty intrinsic in the Monte Carlo method to reproduce transverse fluctuations and correlations in a fully parametrized simulation. (orig.)

[en] The problem of fluctuations on the charged track length by electromagnetic cascades in an absorber of finite thickness is investigated by means of a model. General expressions for the deterioration of the energy resolution are derived and compared with the predictions of the (electron-gamma shower) code for radiation transport

[en] By using a neural network classifier, we are able to identify simulated decays of the Z⁰ boson into banti b pairs with ≅ 85% efficiency, and with a fraction of misidentified light quark decays of ≅ 45%. The simulation takes into account the experimental inefficiencies and resolutions typical of a LEP detector, and makes use of the reconstruction of charged tracks only. (orig.)

[en] A three-dimensional parametrization of photon-initiated showers in a homogeneous absorber is presented. The form, suggested by a model assimilating the transverse shower development to a random walk process, displays a simple scaling with the primary energy, and is very suitable for numerical integration. The parameters are explicitly calculated for the case of showers in SF5 lead glass, and the results are compared with the explicit simulation by GEANT3.11. Fields of application are investigated. (orig.)