Some intriguing aspects of multiparticle production processes

Abstract

Multiparticle production processes provide valuable information about the mechanism of the conversion of the initial energy of projectiles into a number of secondaries by measuring their multiplicity distributions and their distributions in phase space. They therefore serve as a reference point for more involved measurements. Distributions in phase space are usually investigated using the statistical approach, very successful in general but failing in cases of small colliding systems, small multiplicities, and at the edges of the allowed phase space, in which cases the underlying dynamical effects competing with the statistical distributions take over. We discuss an alternative approach, which applies to the whole phase space without detailed knowledge of dynamics. It is based on a modification of the usual statistics by generalizing it to a superstatistical form. We stress particularly the scaling and self-similar properties of such an approach manifesting themselves as the phenomena of the log-periodic oscillations and oscillations of temperature caused by sound waves in hadronic matter. Concerning the multiplicity distributions we discuss in detail the phenomenon of the oscillatory behaviour of the modified combinants apparently observed in experimental data.

A Look at Multiplicity Distributions via Modified Combinants

“…However, such a procedure only improves the agreement at large , whereas the ratio = / still deviates dramatically from unity at small for all fits [4,5]. This means that the measured ( ) contains information which is not yet captured by the rather restrictive recurrence relation (5). Therefore, in [4] we proposed to use a more general form of the recurrence relation (used, for example, in counting statistics when dealing with multiplication effects in point processes [21]):…”

“…Both features were only rarely used as a source of information. We demonstrate that the modified combinants can be extracted experimentally from the measured ( ) by means of a recurrence relation involving all ( < ), and that new information is hidden in their specific distinct oscillatory behavior, which, in most cases, is not observed in the obtained from the ( ) commonly used to fit experimental results [4][5][6][7]. We discuss the possible sources c ○ M. RYBCZYŃSKI, G. WILK, Z. W LODARCZYK, 2019 of such behavior and the connection of the with the enhancement of void probabilities, and their impact on our understanding of the multiparticle production mechanism, with emphasis on understanding both phenomena within the class of compound distributions.…”

Intriguing properties of multiplicity distributions

“…Nevertheless, it seems that some of their properties remain unnoticed or unused as a possible source of such information. In this work we analyse the non-single diffractive (NSD) charged multiplicity distributions concentrating on two features: (i) on the observation that, after closer inspection, they show a peculiarly enhanced void probability, P (0) > P (1) [2,3], and (ii) on the oscillatory behavior of the so called modified combinants, C j , introduced by us in [4,5]. We demonstrate how these modified combinants can be extracted experimentally from the measured P (N ) by means of some recurrence relation involving all P (N < j), and argue that they contain information (located mainly in the small N region) which was so far not disclosed and used.…”

Modified combinant analysis of the e+e− multiplicity distributions

“…Recently it was shown that the measured multiplicity distributions, P (N ), contain some additional information on the multiparticle production process, so far undisclosed. [1][2][3][4] The basic idea was to apply the recurrence relation used in counting statistics when dealing with multiplication effects in point processes. 5 Its important feature is that it connects all multiplicities by means of some coefficients C j (modified combinants), which define the corresponding P (N ) in the following way:…”