Wang Shaoshun

Self-Affine Multifractal Spectrum and Levy Stability Index from NA27 Data

A self-affine analysis of multiparticle production in pp collisions at 400 GeV/c was performed by using the method of continuously varying scale and the method of the factorial moments of continuous order. The self-affine generalized fractal dimensions and multifractal spectrum have been obtained. The self-affine multifractal spectrum is a concave downward with a maximum at q = 0, f(α(0)) = D(0) = 1. D(q) decreases with increasing q showing that there is self-affine multifractal behaviour in multiparticle production at the 400 GeV/c pp collisions. The levy index µ>1 indicates that a non-thermal phase transition may exist in the pp collisions at 400 GeV/c. PACS: 13. 85. Hd

THE MEASUREMENT OF ENTROPY INDICES IN PP COLLISIONS AT 400 GEV/C

Abstract The entropy indices are calculated from the data of 400 GeV/ c pp collisions. The entropy indices are increased with decreasing average multiplicities of the final states.

NON-THERMAL PHASE TRANSITION IN PP COLLISIONS AT 400 GEV/C?

Abstract Factorial moments are calculated up to order q =7 by the star integral method for the data of pp collisions at 400 GeV/ c . Multifractality is observed in hadroproduction supporting a cascading scenario of particle production. The intermittency indices φ q and the behavior of the function λ q =( φ q +1)/ q indicate a possible non-thermal phase transition and two different regimes of multiparticle production.

Factorial moments of continuous order for multiparticle production in 400 GeV/c pp collisions

Abstract Dynamic fluctuations in normalized pseudorapidity space with very small bin size are studied for 400 GeV/ c pp collisions using factorial moments of continuous order. The fractal dimension D ( q ) and the multifractal spectrum f ( α ) are presented. The observed hierarchy D (0) > D (1) > D (2) provides evidence for multifractal behavior in multiparticle production.

Factorial correlators and cumulant correlators in pp collisions at 400 GeV/c

Abstract Factorial correlators and cumulant correlators are studied in 400 GeV/ c pp collisions as a function of bin-bin distance. A power-law behaviour has been found in a certain range of bin-bin distances. The sun-rules which are based on translation invariance have been tested. The second-order cumulant correlators show that the two-particle correlation may weakly depend on the average multiplicity.

Split-Bin Correlation Functions for Multi-Particle Processes in PP Collisions at 400 GeV/c

The pseudorapidity and azimuthal angle distributions for charged particle produced in pp collisions at 400 GeV/c have been measured by using the LEBC films offered by CERN NA27 collaboration. The split-bin correlation functions have been calculated. The results show that the correlations are produced by resonance-like processes.

BUNCHING PARAMETERS AND CORRELATORS IN 400 GEV/C PP COLLISIONS

Abstract The multiplicity fluctuations of charged particles produced in pp collisions at 400 Gev/ c have been studied by means of the bunching parameters (BPs) and bunching correlators. The results show that the values of BPs η 2 ( M ) and η 3 ( M ) depend not only on the width of multiplicity distribution, but also on the phase space correlations. The BPs η 2 ( M ) and η 3 ( M ) follow the same power-law behavior indicating multifractal structure in pp collisions at 400 GeV/ c . The values of the second-order bunching correlators depend on the width of multiplicity distributions and decrease with increasing bin-bin distance D .

Angular dependence of particle correlations in pp collisions at 400 GeV/c

Abstract The angular dependence of the particle-particle correlation (PPC) and its asymmetry (PPCA) has been studied by using the experimental data of multiplicity production for pp collisions at 400 GeV/ c . The results differ strongly from the overall behavior of e + e − data, but agree with the results obtained by NA22 Collaboration quite well.

Cumulant Correlators and Azimuthal Correlations in PP Collisions at 400 GeV/c

The cumulant correlators and azimuthal correlations of particles produced in protonproton (PP) collisions at 400 GeV/c are investigated. The second-order cumulant correlators show that the two particle correlation length may be determined by comparing the experimental data with the Monte Carlo events sample which has same multiplicity distributions but no correlation. The azimuthal correlation has also been observed.

Factorial Cumulant Moments and Short Range Correlation in P-P Collisions at 400 GeV/c

The pseudorapidity distribution of charged particles produced in p-p collisions at 400 GeV/c was measured by using the Lexan bubble chamber films offered by the CERN NA27 collaboration. The scaled factorial cumulant moments have been calculated. The results show that the second order cumulants have positive values, while the cumulants of higher order are consistent with zero except for the case with nch ≥ 4 events, where the third-order cumulants have small positive values beyond the statistical uncertainties. From Monte Carlo events with the same single particle spectrum and no correlations, we observed that for broad mixed-multiplicity distributions, a significant part of K2 is coming from the single-particle fluctuation due to the fluctuation multiplicity.