It is understood that multiplicity fluctuations serve as one of the important observables for the study of the critical endpoint in the beam energy scan program of RHIC.
As a matter of fact, the problem is rather subtle, and many different factors may potentially affect the observable in question.
In this work, we take into consideration the thermal fluctuations, resonance decay, as well as the hydrodynamic expansion of the system.
In particular, we focus on the noncritical aspects of the topic and investigate the multiplicity fluctuations in heavy-ion collisions by using a hydrodynamic model.
Subsequently, we evaluate the effects of initial state fluctuations and resonance decay.
The obtained results are compared to those obtained by the statistical model as well as the experimental data.