Regular Series


Vol. 5 (1974), No. 1 – 2, pp. 3 – 152


The Statistical Description of Multihadron Production Processes

abstract

The statistical approach to multihadron production processes assumes that the relative probability for different inclusive final states is determined by the corresponding level densities. The proposed statistical descriptions can be divided into two classes: purely statistical models (Fermi model, Pomeranchuk model, uncorrelated jet model, statistical bootstrap model), and hybrid models, which combine non-statistical cluster formation with statistical cluster decay (two- and multi-center models, thermodynamical model, nova and multinova models, diffraction fragmentation models). After a survey of the various models with comments on their interrelation, we discuss in particular asymptotic phase space behaviour, the solution of the statistical bootstrap equation, the dynamical interpretation of this solution in terms of resonance interactions, and the connection between the statistical bootstrap approach and aspects of the dual resonance model.


Duality and Regge Analysis of Inclusive Reactions. Part I

abstract

The application of duality to analysis of inclusive spectra in fragmentation and central regions is discussed.


Duality and Regge Analysis of Inclusive Reactions. Part II

abstract

Recent developments in triple Regge analysis of inclusive spectra are presented, with particular emphasis on application of the finite mass sum rules.


Stable Causality of Highly Mobile Space-Times

abstract

Each highly mobile, algebraically special space-time is shown to possess a global time function. It follows from this that these space-times are stably causal.


Study of Dual Diffractive Models in Process pp \(\to \) pn \(\pi ^+\) at 12 GeV/\(c\)

abstract

The Pokorski–Satz and the Dorren–Rittenberg–Yaffe models for diffractive process pp \(\to \) pn \(\pi ^+\) at 12 GeV/\(c\) are tested. The Dorren–Rittenberg–Yaffe model is tested with 0.0, 0.3, and 0.5 pomeron slopes. This model has only two free parameters (the overall normalization constant and relative coupling constant) and gives a reasonably good agreement with the data for the pomeron slope of 0.3 and 0.5. In particular, it gives the correct angular distributions in the Gottfried–Jackson angle on the n\(\pi ^+\) system. The distribution in azimuthal angle \({\mit \Phi }(n\pi ^+)\) in Gottfried–Jackson and helicity frames are not flat which means that helicity is not conserved both neither in \(t\)- nor in \(s\)-channels. The Pokorski–Satz model also reasonably describes the data except for the angular distributions in the Gottfried–Jackson frame.


Theoretical Cross-Sections of Single \(W\)-Boson Production in Photon–Electron Collisions and in Electron–Positron Colliding Beam Experiments

abstract

Total cross-section for the production of single \(W\)-boson in high energy photon–electron collisions is computed in the limit \(m_e \to 0\). Applying the Weizsäcker–Williams approximation, we obtain the asymptotic formulae for the total cross-sections of single \(W\)-boson production in high energy electron–positron colliding beam experiments.


The Influence of Isospin Conservation on Pion Multiplicity Distribution in Independent Emission Models

abstract

We discuss two models for multiple pion production in which strict conservation of isospin generates strong correlations in multiplicity distribution. The first model is a particular version of the uncorrelated jet model in which pions are produced in an eigenstate of total isospin and charge, the second one is the hadronic bremsstrahlung model of pion emission by an isospinor nucleon current. The predictions of these models concerning multiplicity distribution are almost identical: 1. linear rise of the dispersion of the negative pion multiplicity distribution with the average multiplicity which agrees with the data very well, and 2. strong negative correlations between charged and neutral pions which is in disagreement with the data.


Charge Collection Method of Total Reaction Cross-Section Measurements for Alpha Particles

abstract

The electric charge collection method was developed for measurements of the total reaction cross-section for the interaction of alpha particles with nuclei. The effect of electron capture by alphas in the target material was reduced by carbon foil placed behind the target. The results for natural targets of Ni, Co, Cu, Pd, Ag, In, Sn, Ta, Pt, Au, Pb, and Bi at alpha particle energies 23.2 MeV and 27.8 MeV are presented.


all authors

A. Bobrowska, A. Budzanowski, K. Grotowski, L. Jarczyk, B. Kamys, A. Kapuścik, J. Płoskonka, A. Strzałkowski, Z. Wróbel, L. Zastawniak, R. Zybert

Statistical Analysis of Excitation Functions for Elastic and Inelastic Scattering of \(\alpha \)-Particles on Mg and Si Nuclei

abstract

The excitation functions for inelastic cc-scattering leading to the low lying excited states in \(^{24}\)Mg and \(^{28}\)Si were measured at \({\mit \Theta }_{\rm LAB}=170^{\circ }\), 175\(^{\circ }\) and 179\(^{\circ }\) in the LAB energy range 22.75–28.40 MeV. Statistical analysis of these excitation functions and those previously measured for elastic scattering was performed. The direct interaction contribution \(y_D\) to the reaction studied was obtained from probability distributions of cross sections and from correlation coefficients. Cross correlation coefficients between different reaction channels were calculated.


Positive \(\pi ^-\)–\(\pi ^0\) Correlation in an Uncorrelated Jet Model

abstract

Any uncorrelated jet model is characterized by the three distributions \(P_0(n)\), \(P_1(n)\) and \(P_2(n)\) for the total number of pions in the final mesonic states with isospin 0, 1 and 2. It is shown that for each number of protons in the final state there exists a scaling function for the total number of charged particles. In \(pp\)-collisions there are three such functions (when pair production is disregarded). A measurement of these three functions would be very important since they completely determine every other distribution and therefore all correlations. It is shown that positive \(\pi ^-\)–\(\pi ^0\) correlations can be obtained from three Poisson-distributions \(P_0(n)\), \(P_1(n)\) and \(P_2(n)\), provided their averages \(\overline {N}_0\), \(\overline {N}_1\) and \(\overline {N}_2\) are not equal. This effect is similar to that of the two component model.


Lagrangians for Massive, Arbitrary Spin Fields

abstract

Explicit Lagrangians for massive, arbitrary spin fields are developed. These Lagrangians lead, by the usual variation, to the field equations and subsidiary conditions for fields describing massive particles of arbitrary spin.


Multipole Radiation in the Bremsstrahlung Model of Multiple Production

abstract

The properties of the inclusive single-particle distribution in the brems- strahlung model are studied for the general form of the point-like current.


ERRATUM for Acta Phys. Pol. B 4, 659 (1973)

Diffractive Dissociation as Shadow Scattering


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