18–22 Sept 2017
Polish Academy of Arts and Sciences
Europe/Warsaw timezone

Virtual photon polarization and dilepton anisotropy in relativistic heavy-ion collisions

20 Sept 2017, 18:20
20m
Karolina Lanckorońska Hall

Karolina Lanckorońska Hall

Speaker

Enrico Speranza (GSI and TU Darmstadt)

Description

We present a general framework for studying the angular anisotropy
of dileptons produced from polarized virtual photons in relativistic
heavy-ion collisions. The spin-anisotropy coefficients
characterizing the angular distribution of the dilepton final state
are introduced and their dependence on the medium evolution via flow
velocity and temperature profiles is obtained.
We illustrate these effects in dilepton production from
quark-antiquark annihilation in the QGP phase and $\pi^+\pi^-$
annihilation in the hadronic phase for a static
uniform medium and for a longitudinally expanding system.
It is shown that the anisotropy coefficients are in general non-zero
in a thermalized medium, and depend on the flow of the medium as
well as on the transverse momentum and invariant mass of the virtual
photon. The present framework can be easily implemented in a
realistic hydrodynamic simulation of relativistic heavy-ion
collisions in order to study the effect of non-trivial medium
properties on dilepton anisotropy.

Primary authors

Enrico Speranza (GSI and TU Darmstadt) Dr Amaresh Jaiswal (GSI / National Institute of Science Education and Research HBNI) Bengt Friman (GSI)

Presentation materials