https://doi.org/10.1140/epjc/s10052-015-3624-1
Regular Article - Theoretical Physics
A study of vorticity formation in high energy nuclear collisions
1
Dipartimento di Fisica e Astronomia, Università di Firenze, Via G. Sansone 1, 50019, Sesto F.no (Firenze), Italy
2
INFN, Sezione di Firenze, Via G. Sansone 1, 50019, Sesto F.no (Firenze), Italy
3
Frankfurt Institute for Advanced Studies (FIAS), Johann Wolfgang Goethe University, Frankfurt am Main, Germany
4
Dipartimento di Fisica e Scienze della Terra, Università di Ferrara, Via Saragat 1, 44100, Ferrara, Italy
5
INFN, Sezione di Ferrara, Via Saragat 1, 44100, Ferrara, Italy
6
INFN, Sezione di Torino, Via P. Giuria 1, 10125, Turin, Italy
7
INAF, Osservatorio Astrofisico di Arcetri, L.go E. Fermi 5, 50125, Florence, Italy
8
Indian Institute of Technology Gandhinagar, Ahmedabad, Gujrat, 382424, India
* e-mail: becattini@fi.infn.it
Received:
23
January
2015
Accepted:
17
August
2015
Published online:
3
September
2015
We present a quantitative study of vorticity formation in peripheral ultrarelativistic heavy-ion collisions at GeV by using the ECHO-QGP numerical code, implementing relativistic dissipative hydrodynamics in the causal Israel–Stewart framework in
dimensions with an initial Bjorken flow profile. We consider different definitions of vorticity which are relevant in relativistic hydrodynamics. After demonstrating the excellent capabilities of our code, which proves to be able to reproduce Gubser flow up to 8 fm/c, we show that, with the initial conditions needed to reproduce the measured directed flow in peripheral collisions corresponding to an average impact parameter
fm and with the Bjorken flow profile for a viscous Quark Gluon Plasma with
fixed, a vorticity of the order of some
/fm can develop at freeze-out. The ensuing polarization of
baryons does not exceed 1.4 % at midrapidity. We show that the amount of developed directed flow is sensitive to both the initial angular momentum of the plasma and its viscosity.
© The Author(s), 2015