  Higher-order cumulants of conserved charge distributions are sensitive
observables to probe the critical fluctuations near QCD critical point in
heavy-ion collisions. Due to high interaction rate, pileup event can be one of
the major sources of background in the measurements of higher-order cumulants.
In this paper, we studied the effects of pileup events on higher-order
cumulants of proton multiplicity distributions using UrQMD model. It is found
that the proposed pileup correction fails if the correction parameters are
determined by the Glauber fitting of charged particle multiplicities, which is
usually done in the real heavy-ion experiment. To address this, we propose a
model independent unfolding approach to determine the parameters in the pileup
correction. This approach can be applied in the pileup correction for the
future measurement of higher-order cumulants in heavy-ion collision experiment.

Data Analysis, Statistics and Probability;High Energy Physics - Experiment;High Energy Physics - Phenomenology;Nuclear Experiment;Nuclear Theory