Possibility of DCC formation in pp collisions at LHC energy via reaction-diffusion equation

TL;DR

This paper investigates the potential formation of disoriented chiral condensates in high-multiplicity proton-proton collisions at LHC energies, using reaction-diffusion equations to model the chiral field dynamics during rapid expansion and cooling.

Contribution

It introduces a reaction-diffusion equation approach to study chiral field dynamics, suggesting conditions for large DCC domain formation in pp collisions.

Findings

Large DCC domains are likely to form in high-multiplicity pp collisions.

Rapid expansion and cooling can lead to spontaneous chiral symmetry breaking.

Reaction-diffusion equations effectively model the chiral field evolution.

Abstract

There are indications of formation of a thermalized medium in high multiplicity pp collisions at LHC energy. It is possible that such a medium may reach high enough energy density/temperature so that a transient stage of quark-gluon plasma, where chiral symmetry is restored, may be achieved. Due to rapid 3-dimensional expansion, the system will quickly cool undergoing spontaneous chiral symmetry breaking transition. We study the dynamics of chiral field, after the symmetry breaking transition, for such an event using reaction-diffusion equation approach which we have recently applied for studying QCD transitions in relativistic heavy-ion collisions. We show that the interior of such a rapidly expanding system is likely to lead to the formation of a single large domain of disoriented chiral condensate (DCC) which has been a subject of intensive search in earlier experiments. We argue that large multiplicity pp collisions naturally give rise to required boundary conditions for the existence of slowly propagating front solutions of reaction-diffusion equation with resulting dynamics of chiral field leading to the formation of a large DCC domain.