G.I. Orlova

A study of inelastic pion-nucleus interactions at 200 GeV/c in an emulsion

Abstract Results from a study of π-nucleus interactions in emulsion, at an incident momentum of 200 GeV/c are presented and discussed. Some characteristics of heavy and shower-particle multiplicity distributions are reported and compared with the results from p-nucleus collisions at the same momentum. The angular distributions of shower particles are reported and analyzed in detail. It is shown, particularly, that one-particle distributions, being plotted in terms of pseudorapidity, have a bimodal structure in πA interactions. Also, pseudorapidity and azimuthal two-particle correlations are investigated. Considerable attention has been devoted to the exclusion of kinematical and trivial correlations. A qualitative comparison of the data with predictions of some model approaches has been performed.

Investigation of inelastic interactions of 400 GeV protons with emulsion nuclei

Abstract The basic experimental characteristics of incoherent interactions of 400 GeV protons on emulsion nuclei, such as the multiplicity of charged secondaries, one-particle distributions and two-particle correlations, are reported and discussed in details. They are compared with the results of other experiments on hadron-nucleus interactions at lower energies. We have shown from both the quantitative and qualitative comparison of the data presented with predictions of various model approaches to nuclear production, that most of them cannot explain the complete set of experimental observations. An analysis of the experimental data presented gives strong support to the idea that the production mechanism in high-energy hadron-nucleus interactions has two or multi-component character.

Multiplicities and rapidity densities in 200 A GeV 16O interactions with emulsion nuclei

Abstract We report on an experiment in which emulsion chambers were exposed to a beam of 200 A GeV 16 O at the CERN SPS. Pseudo-rapidity distributions are measured with high precision. Pseudo-rapidity densities of 140 particles per unit rapidity corresponding to an energy density of about 3 GeV/fm3 are observed. Pseudo-rapidity density distributions and fluctuations are found to satisfactorily agree with the Lund Monte Carlo model Fritiof, although new and unknown sources for fluctuations might still be present.

On intermittency in heavy-ion collisions and the importance of γ-conversion in a multi-dimensional intermittency analysis

Non-statistical fluctuations are used to probe the dynamical behaviour of multi-particle production in heavy-ion interactions at ultra-relativistic energies. In a one-dimensional analysis a 1〈ϱ〉-scaling is established and it is furthermore found that effects from higher-order particle correlations are small. In a two-dimensional analysis it is shown that a small background of particle pairs with a narrow opening angle can distort the observed signal. As an example we estimate the influence of γ-conversion and find that in our experiment γ-conversion alone gives results consistent with the experimental observations from a two-dimensional analysis. Whereas a two-dimensional analysis filters events where two particles are extremely close in phase space, the one-dimensional analysis picks out events with particles clustered in pseudorapidity, which are at the same time diluted in the azimuthal plane.

Features of the {sup 9}Be {sup {yields}} 2He fragmentation in an emulsion for an energy of 1.2 GeV per nucleon

The results of investigation of the fragmentation of relativistic nuclei 9Be in an emulsion, which is accompanied by the formation of two 1.2-A-GeV He fragments, are presented. The angular measurements of the 9Be → 2He events are analyzed. The 9Be → 8Be + n fragmentation channel with the decay of 8Be from the ground (0+) and first excited (2+) states into a pair of α particles appears to be dominant.The results of investigations of the relativistic

A search for non-statistical particle density fluctuations in 16O + Ag(Br) and 32S + Au interactions at 200 A GeV

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Energy, target, projectile and multiplicity dependences of intermittency behaviour in high energy O(Si,S) induced interactions

Be nucleus fragmentation in emulsion which entails the production of two He fragments of an energy of 1.2~A~GeV are presented. The results of the angular measurements of the

Fragmentation of 22Ne in emulsion at 4.1A GeV/c

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Multiplicities in84Kr interactions in emulsion at 800–950 MeV/nucleon

Be

ON THE ENERGY AND MASS DEPENDENCE OF THE MULTIPLICITY IN RELATIVISTIC HEAVY-ION INTERACTIONS

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