Quark Matter 2018

Femtoscopic Measurements for Shape-engineered Events in Au+Au Collisions at STAR

15 May 2018, 17:00

2h 40m

First floor and third floor (Palazzo del Casinò)

Poster Correlations and fluctuations Poster Session

Speaker

Benjamin Schweid (Stony Brook University)

Description

Femptoscopic measurements allow access to the spatio-temporal characteristics of the systems produced in relativistic heavy-ion collisions. This poster presents new measurements of the two-pion HBT radii ${\mathrm{R}}_{\mathrm{out}}$, ${\mathrm{R}}_{\mathrm{side}}$ and ${\mathrm{R}}_{\mathrm{long}}$ have been made for shape-engineered events by the STAR experiment. Shape selection was accomplished via cuts on the distributions of the second-order flow vector $Q_2$ \cite{timmins}\cite{lacey}. Selected events, characterized with larger magnitudes of $Q_2$, indicate a systematic decrease for $R_{long}$ and $R_{out}$ with little, if any, change for $R_{side}$. Results obtained as a function of collision centrality and average pair transverse momentum ($k_T$) will be presented for the full range of the Au+Au beam energy scan ($\sqrt{s_{NN}}=7.7-200$ GeV). The implications of these results for expansion dynamics of the collision systems will be discussed.

References
[1] J. Schukraft, A. Timmins, and S. A. Voloshin, Phys. Lett. B719, 394 (2013).
[2] Roy. A Lacey, et. al., J.Phys. G 43 (2016) no.10, 10LT01, arXiv:1311.1728.