Limiting fragmentation in high-energy nuclear collisions at the CERN Large Hadron Collider

TL;DR

This study investigates the limiting fragmentation phenomenon in high-energy nucleus-nucleus collisions at the LHC, revealing that it appears to be violated at these energies when considering energy-dependent inelastic cross-sections.

Contribution

The paper revisits limiting fragmentation in A+A collisions using energy-dependent inelastic cross-sections and AMPT model simulations, showing violations at LHC energies.

Findings

Limiting fragmentation appears violated at LHC energies.

Energy-dependent inelastic cross-sections influence the validity of LF.

AMPT model simulations support LF violation at high energies.

Abstract

The hypothesis of limiting fragmentation (LF) or it is called otherwise recently, as extended longitudinal scaling, is an interesting phenomena in high energy multiparticle production process. This paper discusses about different regions of phase space and their importance in hadron production, giving special emphasis on the fragmentation region. Although it was conjectured as a universal phenomenon in high energy physics, with the advent of higher center-of-mass energies, it has become prudent to analyse and understand the validity of such hypothesis in view of the increasing inelastic nucleon-nucleon cross-section ($\sigma_{\rm in}$). In this work, we revisit the phenomenon of limiting fragmentation for nucleus-nucleus (A+A) collisions in the pseudorapidity distribution of charged particles at various energies. We use energy dependent $\sigma_{\rm in}$ to transform the charged particle pseudorapidity distributions ($dN^{\rm AA}_{ch}/d\eta$) into differential cross-section per unit pseudorapidity ($d\sigma^{\rm AA}/d\eta$) of charged particles and study the phenomenon of LF. We find that in $d\sigma^{\rm AA}/d\eta$ LF seems to be violated at LHC energies while considering the energy dependent $\sigma_{\rm in}$. We also perform a similar study using A Multi-Phase Transport (AMPT) Model with string melting scenario and also find that LF is violated at LHC energies.