Directed flow of $\phi$ mesons in Au+Au collisions at the second phase of beam energy scan (BES-II) program from STAR

    The \(\phi\) meson is composed of strange quarks (\(s\overline s\)) and has a small hadronic interaction cross-section, which reduces the influence of late stage rescattering in heavy-ion collisions.

    Thus the directed flow ($v_{1}$) of \(\phi\) mesons is sensitive to the early stages of the collisions and is an important observable for the study of QCD phase diagram at RHIC. In this talk, we will present measurements of directed flow of \(\phi\) mesons in Au+Au collisions at $\sqrt{s_{NN}}=3,\ 7.2,$ and $19.6$ GeV from the second phase of RHIC beam energy scan (BES-II) program. \(\phi\) mesons are reconstructed through the decay channel \(\phi\rightarrow K^{+}+ K^{-}\). We will compare our new results with the BES-I results.