Family of New Exact Solutions for Longitudinally Expanding Ideal Fluids

TL;DR

This paper introduces a new family of exact analytical solutions for longitudinally expanding ideal fluids, relevant for modeling high-energy nuclear collisions, and demonstrates their consistency with experimental data.

Contribution

It presents novel analytical solutions for relativistic ideal hydrodynamics with plateau structures, extending previous models and matching experimental rapidity distributions.

Findings

Solutions match experimental rapidity distributions

Plateau structures can be symmetric or asymmetric

Provides new tools for modeling high-energy collisions

Abstract

We report on the discovery of new analytical solutions of the equations of relativistic ideal hydrodynamics. In this solution, the fluid expands in the longitudinal direction and contains a plateau structure that extends over a finite range in rapidity and can be either symmetric or asymmetric in that variable. We further calculate the corresponding pseudo-rapidity distribution of hadron yields, and find decent agreement with experimental measurements in high-energy Pb+Pb, Au+Au, p+Pb, and d+Au collisions.