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[en] The data presented here have been collected by the International Hybrid Spectrometer Consortium in the 30'' B.C. hybrid spectrometer exposed to a 147 GeV/C positive tagged beam made of 47% π⁺; 45% p; 8% K⁺(root-bars = 16.7 GeV) at Fermilab. The sample consists of 15802 events with at least 4 prongs (11822 events with at least 6 prongs) fully measured and reconstructed with an accuracy Δp/p<0.5%. To account for second-measurements still to be done, the events are weighted according to the measured topological cross sections. The variables used (Sphericity S and thrust T) are evaluated in a 3-dimensional c.m. momentum space defined by the principal axes resulting from the diagonalization of the 3 x 3 matrix T/sup alphabeta/ = summation/sub i/[p²/sub i/delta/sub alphabeta/-p/sup α//sub i/p/sup β//sub i/]; α,β = x,y,z; p/sup x//sub i/,p/sup y//sub i/,p/sup z//sub i/ are the c.m. momentum components of particle i (x-direction along the beam). Their use in hardron hadron physics was suggested long ago

[en] This paper deals with the ¹³⁷Cs cumulative soil deposition measured in some European Countries after the Chernobyl accident. We devised a multifractal model to aid in describing the spatial distribution of radioactivity. The model is based on the Fractal Sum of Pulses theory, involving additive stochastic processes. We use, as input source of information, the available data of radioactive deposition measured in some European Countries. The results look promising, since realistic scenarios of environmental pollution are produced. (author)

[en] We present here an analysis of the airborne radioactivity measured in Italy after the Chernobyl accident. We provide some quality assurance, isolate suspicious data, and devise a mathematical model to aid in interpreting time-dependent fallout data. The model consists of an interpolating function whose parameters can be related to (1) the arrival time of the radioactive cloud; (2) the time of the maximum radioactive concentration; and (3) the decay-rate of airborne radioactivity as the pollutant cloud passes. Multiple arrivals of the radioactive cloud in a given site can also be considered. The parametrization can be used to estimate concentrations of ¹³⁷Cs using measurements of ¹³¹I, ¹⁰³Ru, or ¹³²Te. The interpolating function is fitted to the data collected in several Italian Provinces. We feel this model is an useful tool for interpreting time-dependent fallout data. 13 refs., 7 figs., 13 tabs

[en] This paper deals with the ¹³⁷Cs airborne radioactive concentration measured in Northern Italy after the Chernobyl accident. We devised a fractal model to aid in describing the space-time distribution of radioactivity. The model is based on the Fractal Sum of Pulses theory, involving additive stochastic processes. We use, as input source of information, the parametrization of the time trend of radioactive concentration in a few Italian Provinces we calculated in previous work. The results look promising, since realistic scenarios of environmental pollution are produced. (Author)

[en] Authors present an analysis of the net charge density distributions in π^-p collisions at 11.2 GeV/c studying how electric charge gets distributed for different topologies as a function of rapidity and transverse momentum. The experimental data have been collected in approximately 850.000 picture exposure of the CERN 2m hydrogen bubble chamber to a π^- beam of 11.2 GeV/c. The structures of charge density distributions are complex and an appealing explanation is the leading particle effect and/or diffraction dissociation present in two and four prongs, but not in six prongs

[en] FOCUS collected over 7 x 10⁷ and more than 10⁶ fully reconstructed charm particles in a photoproduction experiment at Fermilab. The experimental setup is an upgraded version of a multiparticle spectrometer used in the previous experiment E687. Data on charmed meson spectroscopy have been presented by F.L. Fabbri in this Section. Here data on photoproduction of charmed baryons are presented. (author)

[en] In the present paper we give the experimental measurement of the cross section per nucleon for the elastic J/ψ photoproduction in six energy intervals from 100 GeV to 450 GeV; the overall dσ/dt differential cross section, as well as an estimate of the coherent diffractive photoproduction off the Be nucleus. We will finally compare the energy dependence of our measured cross sections with the predictions of the PGF Model

[en] In this paper we analyze a part of R.E.M., the European Data Bank which contains, among others, all measurements of the radioactive pollution in air due to the Chernobyl accident. A parametric function is fitted to the measured values of the radionuclides' concentration in air (in Bq/m³) in several location in Italy and in France. The data are cleaned from trivial errors and properly handled; a method to homogenize the parameters' values is proposed. We show how to modify the interpolating function in order to account for multiple arrivals of the pollutant clouds. We estimated from the data the arrival times of the radioactive clouds and compare our results for ¹³⁷Cs to the predictions of a Long Range Transport Model developed by a group at SRD-UKAEA. Finally we present the preliminary results of a Fractal model designed to describe the air radioactivity distribution in a limited area in Northern Italy

[en] In the first part of this paper the variable sets most commonly used in high-energy hadronic physics are reviewed. It is shown that, when more and more particle are involved, particular sets of variables turn out to be more suitable than others to describe experimental facts and to investigate the interaction dynamics. In the second part hadronic diffraction, both elastic and inelastic, Fraunhofer diffraction is discussed, a semi-classical optical picture being the starting point. Finally, in the third part, second order interference phenomena, known as Hanbury-Brown and Twin phenomena, are considered, and their relevance to a better understanding of the production mechanism in multiparticle physics is pointed out