https://doi.org/10.1140/epjc/s10052-012-2143-6
Regular Article - Theoretical Physics
Net-baryon-, net-proton-, and net-charge kurtosis in heavy-ion collisions within a relativistic transport approach
1
SUBATECH, UMR 6457, Université de Nantes, Ecole des Mines de Nantes, IN2P3/CRNS, 4 rue Alfred Kastler, 44307, Nantes cedex 3, France
2
Frankfurt Institute for Advanced Studies (FIAS), Ruth-Moufang-Str. 1, 60438, Frankfurt am Main, Germany
3
Institut für Kernphysik, Johann Wolfgang Goethe-Universität, Max von Laue-Str. 1, 60438, Frankfurt am Main, Germany
4
Institut für Theoretische Physik, Johann Wolfgang Goethe-Universität, Max-von-Laue-Str. 1, 60438, Frankfurt am Main, Germany
* e-mail: nahrgang@fias.uni-frankfurt.de
Received:
30
May
2012
Revised:
13
July
2012
Published online:
6
September
2012
We explore the potential of net-baryon, net-proton and net-charge kurtosis measurements to investigate the properties of hot and dense matter created in relativistic heavy-ion collisions. Contrary to calculations in a grand-canonical ensemble we explicitly take into account exact electric and baryon charge conservation on an event-by-event basis. This drastically limits the width of baryon fluctuations. A simple model to account for this is to assume a grand-canonical distribution with a sharp cut-off at the tails. We present baseline predictions of the energy dependence of the net-baryon, net-proton and net-charge kurtosis for central (b≤2.75 fm) Pb+Pb/Au+Au collisions from E
lab=2A GeV to 
from the UrQMD model. While the net-charge kurtosis is compatible with values around zero, the net-baryon number decreases to large negative values with decreasing beam energy. The net-proton kurtosis becomes only slightly negative for low 
.
© Springer-Verlag Berlin Heidelberg and Società Italiana di Fisica, 2012
