QM 2011 - XXII International Conference on Ultrarelativistic Nucleus-Nucleus Collisions

May 22 – 28, 2011
Centre Bonlieu
Europe/Zurich timezone

Net-baryon-, net-proton-, and net-charged particle kurtosis in heavy-ion collisions within a relativistic transport approach

May 27, 2011, 7:10 PM
20m
Salon Berlioz AB (Imperial Palace)

Salon Berlioz AB

Imperial Palace

Allée Impérial 74000 Annecy, France Tél. : +33 4 50 09 30 00
Parallel QCD phase diagram

Speaker

Marlene Nahrgang (Goethe University Frankfurt and Frankfurt Institute for Advanced Studies (FIAS))

Description

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 Poisson distributions 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 ($b\leq 2.75$~fm) Pb+Pb/Au+Au collisions from $E_{lab}=2A$~GeV to $\sqrt{s_{NN}}=200$~GeV 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 $\sqrt{s_{NN}}$.

Primary authors

Marcus Bleicher (Frankfurt Institute for Advanced Studies(FIAS)) Marlene Nahrgang (Goethe University Frankfurt and Frankfurt Institute for Advanced Studies (FIAS)) Michael Mitrovski (Physics Dept.,BNL, Brookhaven) Reinhard Stock (Frankfurt Institute for Advanced Studies(FIAS) and Institut fuer Kernphysik, University of Frankfurt) Tim Schuster (Frankfurt Institute for Advanced Studies(FIAS) and Institut fuer Kernphysik, University of Frankfurt)

 Slides