# Elliptic flow of identified hadrons in Au+Au collisions at $E_{lab} = 35\mathrm{~A~GeV}$ using the PHSD model

## TL;DR

This paper investigates the elliptic flow ($v_2$) of identified hadrons in Au+Au collisions at 35A GeV using the PHSD model, revealing centrality dependence, particle-antiparticle differences, and the influence of partonic interactions.

## Contribution

It provides detailed predictions of $v_2$ behavior, including NCQ scaling and mode comparisons, highlighting the role of partonic medium formation at this energy.

## Key findings

- Higher $v_2$ in PHSD mode indicates partonic medium formation.
- Significant $v_2$ difference between particles and antiparticles.
- Centrality dependence of $v_2(p_T)$ observed.

## Abstract

We present elliptic flow ($v_2$) of identified hadrons at mid-rapidity ($|y| < 1.0$) in Au+Au collisions at $E_{lab} = 35\mathrm{~A~GeV}$ using the Parton Hadron String Dynamics (PHSD) model. Transverse momentum ($p_\mathrm{T}$) dependence of identified hadron $v_2$ in minimum bias (0-80%) and three different centrality intervals (0-10%, 10-40%, and 40-80%) are presented. A clear centrality dependence of $v_2(p_\mathrm{T})$ is observed for particles and anti-particles in Au+Au collisions at $E_{lab} = 35\mathrm{~A~GeV}$. We also present $p_\mathrm{T}$ dependence of $v_2$ difference ($\mathrm{\Delta} v_2$) between particles and corresponding antiparticles. A significant difference in $v_2$ values for baryons and anti-baryons is observed. The number of constituent quark (NCQ) scaling of $v_2$ is discussed in Au+Au collisions at $E_{lab} = 35\mathrm{~A~GeV}$. We also present ratio of $v_2(p_\mathrm{T})$ between the HSD and PHSD modes to explore the effect of hadronic and partonic interactions in the medium. We observe higher $v_2$ in PHSD mode than the HSD mode, which suggests the formation of partonic medium in Au+Au collisions at $E_{lab} = 35\mathrm{~A~GeV}$. These predictions are useful for the interpretation of data measured in Beam Energy Scan (BES) program at RHIC and will be useful for the future Compressed Baryonic Matter (CBM) experiment at the Facility for Antiproton and Ion Research (FAIR).