  The rapidity-odd component of directed flow ($v_{1}$) of identified hardons
($\pi^{\pm}$, $K^{\pm}$, $K^{0}_{S}$, $p$, $\bar{p}$, $\phi$, $\Xi$,
$\bar{\Xi}$, $\Lambda$, $\bar{\Lambda}$) and partons ($u$, $\bar{u}$, $d$,
$\bar{d}$, $s$, $\bar{s}$) in Au+Au collisions at various beam energies
($\sqrt{s_{\rm NN}}$ = 7.7, 11.5, 14.5, 19.6, 27, 39, 54.4, 62.4, 200 GeV)
using a multi-phase transport model is analyzed. A data driven approach
(inspired from the experimental analysis) is performed here to distinguish the
transported and produced quarks which are found to have different directed flow
values at various collision beam energies. The coalescence sum rule (Number of
Constituent Quark scaling) violation is observed at lower energies where
hadronic matters dominate. The strange quark ($s$) and $\phi$ meson slope
(d$v_{1}$/d$y$) show a double sign change around 14.5 GeV, unlike other partons
and hadrons. It suggests that strange quark is more sensitive to the softening
of Equation of State (EoS).

Nuclear Experiment