Study on the Influence of Non-flow Contribution on Elliptic Flow in d-Au Collision Using AMPT Model

The AMPT (A Multi-Phase Transport) model is employed to investigate the elliptic flow (v_2^) of charged hadrons produced in d-Au collisions at a collision energy of 200 GeV. The influence of non-flow sources, including jet fragments and resonance decays, on v_2^ in this small collision system is systematically examined. A non-flow contribution subtraction method is adopted, in which the charged hadron yield in central d-Au collisions (centrality 0~5%) is subtracted from that in peripheral d-Au collisions (centrality 60%~100% or 80%~100%) or in pp collisions at the same collision energy, in order to suppress non-flow effects. The dependence of the extracted v_2^ on different subtraction schemes is analyzed. It is found that theoretical calculations with non-flow contributions removed provide an improved description of existing experimental data, while the results obtained from different subtraction schemes show good consistency. The study demonstrates that the choice of peripheral d-Au collisions or pp collisions as the subtraction reference has only a minor influence on the final theoretical predictions. These results provide a theoretical basis for the removal of non-flow contributions in small collision systems and offer useful guidance for related experimental analyses.