Insight from the elliptic flow of identified hadrons measured in relativistic heavy-ion collisions

Abstract

In this paper, we have discussed the transverse momentum dependence of elliptic flow measured in relativistic heavy-ion collisions. The transverse momentum dependence of the number of constituent quarks ($n_{q}$) scaled $v_{2}$ is obtained for all the measured identified hadrons. The $n_{q}$ scaled $\phi$ $v_{2}$ is found to be similar to $n_{q}$ scaled $\Omega$ $v_{2}$. This indicates that both $\phi$ and $\Omega$ are produced through quark recombination at RHIC energies. We also find $n_{q}$ scaled proton $v_{2}$ ($v_{2}$ of light quarks) is higher than $n_{q}$ scaled $\phi$ and $\Omega$ $v_{2}$ ($v_{2}$ of strange quarks) at $p_{T}/n_{q}$ $<$ 1.0 GeV/c. This can be explained by considering quark $v_{2}$ is proportional to its transverse kinetic energy considering mass of deconfined light and strange quarks equal to $\sim $4 MeV and $\sim$ 140 MeV, respectively.