$v_{n}$ measurement in Au+Au collisions at $\sqrt{s_{NN}} =$ 27 GeV with the Event Plane Detector from STAR

The measurement of pseudorapidity ($\eta$) dependence of $v_{n}$ at lower collision energies can provide unique constraints on the three-dimensional initial conditions, baryon transport, shear viscosity over entropy density as well as its dependence on temperature and baryon chemical potential. The combination of the Event Plane Detector (EPD, $2.1<|\eta|<5.1$) installed in the year 2018, STAR time projection chamber (TPC, $|\eta|<1$) and high statistics Beam Energy Scan phase-II data enables us to perform precise measurements of $v_{n}(\eta)$. In this presentation,I will talk about the measurement of directed flow ($v_{1}(\eta)$) and elliptic flow ($v_{2}(\eta)$) of charged hadrons.