STAR Flow, Chirality and Vorticity PWG

["Liu, Xiaoyu" <liu.6566 AT buckeyemail.osu.edu>]

Dear FCV convenors, 

I am interested in submitting an abstract for a talk at Quark Matter 2023. Here is the title and a brief abstract.

Title: Measurement of directed flow at forward and backward pseudorapidity in Au+Au collisions at STAR

Abstract: Directed flow describes the collective sideward motion of produced particles and nuclear fragments in heavy-ion collisions. The pseudorapidity ($\eta$) dependence of $v_{1}$ can provide unique constraints on the initial conditions and dynamical evolution of the Quark Gluon Plasma (QGP). Directed flow in both spectator and participant regions is sensitive to early non-equilibrium dynamics and may provide insights into the baryon stopping mechanism. In 2018, the Event Plane Detector (EPD, $2.1 <|\eta|< 5.1$) was installed in STAR and used for the Beam Energy Scan phase-II (BES-II) data taking. The combination of EPD and high statistics BES-II data enables us to extend the v1 measurement to a wide pseudorapidity range, allowing us to test the phenomenon of limiting fragmentation. In this talk, I will present the measurement of v1 over six units of $\eta$ in Au+Au collisions at $\sqrt{s_{NN}}$=27 and 19.6 GeV and compare the results with multiple physics models. 

Thanks, 

Xiaoyu