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

Abstract

The hypothesis of limiting fragmentation (LF), or, as it has been otherwise recently called, longitudinal scaling, is an interesting phenomena in the high-energy multiparticle production process. This paper discusses 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 analyze and understand the validity of such a hypothesis in view of the increasing inelastic nucleon-nucleon cross section (σin). 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 σin to transform the charged-particle pseudorapidity distributions (dNchAA/dη) into differential cross section per unit pseudorapidity (dσAA/dη) of charged particles and study the phenomenon of LF. We find that in dσAA/dη LF seems to be violated at Large Hadron Collider (LHC) energies while considering the energy-dependent σin. We also perform a similar study using the A Multi-Phase Transport model with a string melting scenario and also find that LF is violated at LHC energies. © 2019 authors. Published by the American Physical Society.