Rapidity dependence of particle densities in pp and AA collisions in the string percolation approach

I Bautista,S Lunardi,P.G Bizzeti,P Di Nezza,M Chiari,A Dainese,R Menegazzo,J.J Valiente-Dobon,C Bucci,A Nannini,C Signorini

doi:10.1051/epjconf/20146604003

Abstract

We use multiple scattering and energy conservation arguments to describe dn=dnNANA as a function of dn=dnpp in the framework of string percolation. As nuclei are made up of nucleons it is natural to look at nucleus-nucleus (A-A) collisions as resulting from the superposition of nucleon-nucleon (p-p) collisions, in the spirit of Glauber model approach. In the single scattering limit the average number of participating nucleons per nucleus, NA behave incoherently and the multiplicity at low energy corresponds to the wounded nucleon model

Highlights

The equation (1) does not agree in general with data
We address the problem of the energy momentum of the NA valence strings shared by NA4/3 mostly sea strings, by reducing the effective number of sea strings rather than reducing the sea plateau
In the impact parameter plane due to the confinement, the color of strings is confined to small area in transverse space S 1 = πr02 with r0 ∼ .2 − .3 fm, these strings decay into new ones by qq − qqpair production and subsequently hadronize to produce the observed hadrons

Summary

Introduction

The equation (1) does not agree in general with data. At higher energies one has to take into account multiple scattering to obtain dn dn. At higher energies one has to take into account multiple scattering to obtain dn dn In the impact parameter plane the strings appear as disks and as energy-density increases the discs overlap, fuse and percolate, leading to the reduction of the overall color [7][8][9].

Results

Conclusion