Analysis Note: Directed flow $v_1$ of protons in the Xe+Cs(I) collisions at 3.8 AGeV

In this note, we present the directed flow $v_1$ measurements of protons from Xe+Cs(I) collisions at 3.8 AGeV (BM@N run8). We show the datasets, event and track selection cuts, centrality definition, event plane reconstruction and resolution. The $v_1$ results are presented as function of transverse momentum ($p_T$) and rapidity ($y_{cm}$) for 10-30% central Xe+Cs(I) collisions. The systematic uncertainty study will also be presented and discussed. The $v_1$ measurements are compared with results of JAM transport model calculations and published data from other experiments.