Hard QCD probes to quark-gluon plasma

TL;DR

This paper reviews the use of high transverse momentum probes in heavy ion collisions to study quark-gluon plasma, emphasizing the potential of upcoming LHC experiments to explore new QCD regimes.

Contribution

It provides a comprehensive overview of current hard QCD probes in heavy ion collisions and discusses expectations for their application at the LHC.

Findings

RHIC results highlight the importance of high transverse momentum spectra.

Small-x nuclear wave functions may be dominated by saturated color fields.

LHC will significantly expand the phase space for QCD studies.

Abstract

Completely unexplored regimes of QCD, dominated by high-density/temperature effects, are available in heavy ion experiments at collider energies. The successful RHIC program shows how relevant the high transverse momentum part of the spectrum is for the characterization of the properties of the created medium. It points, as well, to interesting properties of the nuclear wave function at small fraction of momentum x, probably dominated by saturated color fields. In both domains, the imminent LHC program will provide a phase space enlarged by orders of magnitude with respect to those studied at RHIC. I will review the present status of hard probes in heavy ion collisions as well as the expectations for the LHC.