Energy dependence of fluctuations in central Pb+Pb collisions from NA49 at the CERN SPS

Abstract

The latest NA49 results on fluctuations of multiplicity and average transverse momentum analyzed on an event-by-event basis are presented for central Pb+Pb interactions over the whole SPS energy range (20 A–158 A GeV). The scaled variance of the multiplicity distribution decreases with collision energy whereas the measure of ⟨pT⟩ fluctuations is small and independent of collision energy. Thus in central Pb+Pb collisions these fluctuations do not show an indication of the critical point of strongly interacting matter.