  Statistical moments of particle multiplicities in heavy-ion collision
experiments are an important probe in the exploration of the phase diagram of
strongly interacting matter and, particularly, in the search for the QCD
critical end point. In order to appropriately interpret experimental measures
of these moments, however, it is necessary to understand the role of
experimental limitations, as well as background contributions, providing
expectations on how critical behavior should be affected by them. We here
present a framework for calculating moments of particle multiplicities in the
presence of correlations of both critical and spurious origins. We also include
effects from resonance decay and a limited acceptance window, as well as
detector efficiency. Although we focus on second-order moments, for simplicity,
an extension to higher-order moments is straightforward.
