  Multiplicity fluctuations of positively, negatively and all charged hadrons
in the forward hemisphere were studied in central Pb+Pb collisions at 20A, 30A,
40A, 80A and 158A GeV. The multiplicity distributions and their scaled
variances are presented in dependence of collision energy as well as of
rapidity and transverse momentum. The distributions have bell-like shape and
their scaled variances are in the range from 0.8 to 1.2 without any significant
structure in their energy dependence. No indication of the critical point in
fluctuations are observed. The string-hadronic model UrQMD significantly
overpredicts the mean, but approximately reproduces the scaled variance of the
multiplicity distributions. The predictions of the statistical hadron-resonance
gas model obtained within the grand-canonical and canonical ensembles disagree
with the measured scaled variances. The narrower than Poissonian multiplicity
fluctuations measured in numerous cases may be explained by the impact of
conservation laws on fluctuations in relativistic systems.

Nuclear Experiment