Imprints of Nonextensivity in Multiparticle Production

The statistical methods based on the classical Boltzmann-Gibbs (BG) approach are at heart of essentially all descriptions of multiparticle production processes. In many cases, however, one observes some deviations from the expected behaviour. It is also known that conditions necessary for the BG statistics to apply are usually satisfied only approximately. Two attitudes are possible in such situations: either to abandon statistical approach trying some other model or to generalise it to the so called nonextensive statistics (widely used in the similar circumstances in many other branches of physics). We shall provide here an overview of possible imprints of non-extensitivity existing both in high energy cosmic ray physics and in multiparticle production processes in hadronic collisions, in particular in heavy ion collisions.Comment: LaTeX, 2 PS files with figures, 14 pages altogether. Invited talk presented by G.Wilk at 6th International Workshop on Relativistic Aspects of Nuclear Physics (RANP2000), Caraguatatuba, Tabatinga Beach, Sao Paulo, Brazil, October 17-20, 2000. To be published in the proceedings (World Scientific, Singapore). Minor changes, references update

Non-exponential decays and nonextensivity

We demonstrate that non-exponential decays of unstable systems can be understood as yet another example of nonextensivity encountered in many physical systems and as such can be characterized by the nonextensivity parameter q.Comment: LaTex file only, 8 pages, no figures. Corrected version, to be published in Phys. Lett.

Sound waves in hadronic matter

We argue that recent high energy CERN LHC experiments on transverse momenta distributions of produced particles provide us new, so far unnoticed and not fully appreciated, information on the underlying production processes. To this end we concentrate on the small (but persistent) log-periodic oscillations decorating the observed $p_T$ spectra and visible in the measured ratios $R = \sigma_{data}\left( p_T\right)/\sigma_{fit}\left( p_T\right)$. Because such spectra are described by quasi-power-like formulas characterised by two parameters: the power index $n$ and scale parameter $T$ (usually identified with temperature $T$), the observed log-periodic behaviour of the ratios $R$ can originate either from suitable modifications of $n$ or $T$ (or both, but such a possibility is not discussed). In the first case $n$ becomes a complex number and this can be related to scale invariance in the system, in the second the scale parameter $T$ exhibits itself log-periodic oscillations which can be interpreted as the presence of some kind of sound waves forming in the collision system during the collision process, the wave number of which has a so-called self similar solution of the second kind. Because the first case was already widely discussed we concentrate on the second one and on its possible experimental consequences.Comment: 10 pages, 4 figures. Presented at the XLVII International Symposium on Multiparticle Dynamics (ISMD2017) held in Tlaxcala City, Mexico, during September 11-15, 201

Tsallis statistics approach to the transverse momentum distributions in p-p collisions

Transverse momentum distributions of negatively charged pions produced in p-p interactions at beam momenta 20, 31, 40, 80 and 158 GeV/c are studied using the Tsallis distribution as a parametrization. Results are compared with higher energies data and changes of parameters with energy are determined. Different Tsallis-like distributions are compared.Comment: 6 pages, 9 figure

Oscillations in counting statistics

The very large transverse momenta and large multiplicities available in present LHC experiments on pp collisions allow a much closer look at the corresponding distributions. Some time ago we discussed a possible physical meaning of apparent log-periodic oscillations showing up in p_T distributions (suggesting that the exponent of the observed power-like behavior is complex). In this talk we concentrate on another example of oscillations, this time connected with multiplicity distributions P(N). We argue that some combinations of the experimentally measured values of P(N) (satisfying the recurrence relations used in the description of cascade-stochastic processes in quantum optics) exhibit distinct oscillatory behavior, not observed in the usual Negative Binomial Distributions used to fit data. These oscillations provide yet another example of oscillations seen in counting statistics in many different, apparently very disparate branches of physics further demonstrating the universality of this phenomenon.Comment: Invited talk at ISMD2016, Seogwipo, Jeju Island, South Korea, 29.08-02.09.2016, to be published in EPJ Web of Conference