Blast-wave description of $\Upsilon$ elliptic flow at energies available at the CERN Large Hadron Collider

TL;DR

This paper uses a blast-wave model to describe the elliptic flow of $$ upsilon particles in Pb-Pb collisions at LHC, predicting significant flow only at high transverse momentum due to their large mass.

Contribution

It introduces a compact formula for $v_2(p_T)$ based on the Cooper-Frye ansatz, applied to $$ particles, extending the blast-wave model to heavy quarkonia.

Findings

The model accurately describes $$ elliptic flow data across the full $p_T$ range.

A sizable $$ elliptic flow is predicted only above 10 GeV/$c$ due to its mass.

The approach links light particle flow to heavy quarkonia predictions.

Abstract

A simultaneous blast-wave fit to particle yields and elliptic flow ($v_{2}$) measured as a function of transverse momentum in Pb-Pb collisions at LHC energies is presented. A compact formula for the calculation of $v_2(p_T)$ for an elliptic freeze-out surface is used which follows from the Cooper-Frye ansatz without further assumptions. Over the full available $p_T$ range, the $\Upsilon$ elliptic flow data is described by the prediction based on the fit to lighter particles. This prediction shows that, due to the large $\Upsilon$ mass, a sizable elliptic flow is only expected at transverse momenta above 10 GeV/$c$.