Kinetic temperature and radial flow velocity estimation using identified hadrons and light (anti-)nuclei produced in relativistic heavy-ion collisions at RHIC and LHC

Abstract

We report the investigation of the kinetic freeze-out properties of identified hadrons (${\pi }^{\pm }$, $K^{\pm }$ and $p(\bar{p})$) along with light (anti-)nuclei $d(\bar{d})$, $t(\bar{t})$ and ${}^{3}He$ in relativistic heavy-ion collisions at RHIC and LHC energies. A simultaneous fit is performed with the Blast-Wave (BW) model to the transverse momentum ({\ppt}) spectra of identified hadrons together with light (anti-)nuclei produced in $Au+Au$ collisions at {\sqrtsNN} = 7.7 -- 200 GeV at the RHIC and in $Pb+Pb$ collisions at $\sqrt{{\mathrm{s}}_{{}_{\mathrm{NN}}}}$ = 2.76 TeV at the LHC. The energy and centrality dependence of freeze-out parameters, i.e., kinetic freeze-out temperature ($T_{kin}$) and collective flow velocity $⟨\beta ⟩$ has been studied. It is observed that light (anti-)nuclei also participate in the collective expansion of the medium created in the collision when included in a common fit with the light hadrons. We observe a marginal rise in $T_{kin}$ and a slight decrease in $⟨\beta ⟩$ when compared to the values obtained from the fit to light hadrons. A similar $⟨\beta ⟩$ and significantly larger $T_{kin}$ is observed when a fit is performed to only protons and light (anti-)nuclei. Both, $T_{kin}$ and $⟨\beta ⟩$ show a weak energy dependence at most collision energies.

Comments: 11 pages, 6 figures, 4 Tables