Early evolution of transversally thermalized partons

TL;DR

This paper explores the early stages of heavy-ion collisions, proposing that the created parton system quickly reaches transverse thermal equilibrium and evolves mainly through 2D hydrodynamics, potentially addressing early equilibration issues.

Contribution

It introduces a model where the early evolution of partons is dominated by transverse thermalization and 2D hydrodynamics, offering a new perspective on early equilibration in heavy-ion collisions.

Findings

Transverse thermalization occurs rapidly in the early parton system.

2D hydrodynamics can effectively describe early-time evolution.

This approach may resolve the problem of early thermalization in heavy-ion collisions.

Abstract

The idea that the parton system created in relativistic heavy-ion collisions (i) emerges in a state with transverse momenta close to thermodynamic equilibrium and (ii) its evolution at early times is dominated by the 2-dimensional (transverse) hydrodynamics of the ideal fluid is investigated. It is argued that this mechanism may help to solve the problem of early equilibration.