Speaker
Larisa Bravina
(University of Oslo (NO))
Description
The centrality, rapidity and transverse momentum dependences of
directed flow in light and heavy systems of colliding nuclei are
studied within microscopic transport model QGSM at energies from
10 AGeV to 160 AGeV. The directed flow of pions and kaons has negative
slope at midrapidity irrespective of bombarding energy and mass number
of the colliding ions. In contrast, directed flow of nucleons changes
its slope from normal to antiflow in the midrapidity range in
(semi)peripheral collisions at energies around 11.6 AGeV and higher.
The origin of the flow disappearance is linked to nuclear screening.
Since the effect is stronger for a light system, it can be distinguished
from the similar phenomenon caused by the quark-gluon plasma formation.
Directed flow of high-p_T hadrons has normal slope. To explain it one has
to consider the freeze-out conditions of hadrons in microscopic model.
Author
Larisa Bravina
(University of Oslo (NO))
Co-author
Evgeny Zabrodin
(University of Oslo (NO))
