Speaker
Vipul Bairathi
(National Institute of Science Education and Research)
Description
The main goal of the Beam Energy Scan (BES) Program at RHIC is to study
the structure of the QCD phase diagram. In the years 2010 and 2011 data
were collected for Au+Au collisions at $\sqrt{s_{NN}}$ = 7.7, 11.5,
19.6, 27, 39, 62.4, and 200 GeV. The corresponding baryonic chemical
potential ($\mu_{B}$) ranged from 420 to 20 MeV, leaving a gap of about
100 MeV in the phase space between $\mu_{B}$ = 315 MeV and 205 MeV for
$\sqrt{s_{NN}}$ = 11.5 and 19.6 GeV, respectively. This happened to be
the region of phase space where several interesting observations related
to bulk properties of the system were reported. In the year 2014, Au+Au
collisions at 14.5 GeV (corresponding $\mu_{B}$ for central collisions
$\approx$ 264 MeV) were recorded by the STAR detector.
In this talk we present the first measurements of the transverse
momentum spectra and azimuthal anisotropy of all the identified hadrons
($\pi^{+}$, $\pi^{-}$, $K^{+}$, $K^{-}$, $p(\bar{p})$, $K^{0}_{s}$,
$\Lambda(\bar{\Lambda})$, and $\phi$) at midrapidity in Au+Au collisions
at 14.5 GeV for various collision centralities and compare the results
with those from other BES energies. The bulk properties of the system,
like the chemical freeze-out conditions and the collectivity extracted
from the measured yields of the produced particles will also be
presented. A clear centrality dependence in the difference between
baryon and anti-baryon elliptic flow is observed. Furthermore, the new
data taken at 14.5 GeV show that the baryon-meson splitting of elliptic
flow is of the similar order as for the higher beam energies. The energy
and centrality dependence of the measurements on the bulk properties
will be discussed systematically.
| On behalf of collaboration: | STAR |
|---|
Author
Vipul Bairathi
(National Institute of Science Education and Research)
