Hadron multiplicities, pT-spectra and net-baryon number in central Pb+Pb collisions at the LHC

TL;DR

This paper predicts particle multiplicities, spectra, and net-baryon numbers in central Pb+Pb collisions at LHC energies using pQCD and hydrodynamics, providing key insights into the collision dynamics.

Contribution

It combines pQCD calculations with hydrodynamic modeling to predict detailed particle production and spectra at LHC energies, extending previous models.

Findings

Predicted charged hadron multiplicities and spectra.

Estimated total transverse energy and net-baryon number.

Identified the applicability region of hydrodynamic models.

Abstract

We compute the initial energy density and net baryon number density in 5% most central Pb+Pb collisions at $\sqrt s=5.5$ TeV from pQCD + (final state) saturation, and describe the evolution of the produced system with boost-invariant transversely expanding hydrodynamics. In addition to the total multiplicity at midrapidity, we give predictions for the multiplicity of charged hadrons, pions, kaons and (anti)protons, for the total transverse energy and net-baryon number, as well as for the $p_T$-spectrum of charged hadrons, pions and kaons. We also predict the region of applicability of hydrodynamics by comparing these results with high-$p_T$ hadron spectra computed from pQCD and energy losses.