# Importance of the Volume Fluctuation Correction on Higher Order Cumulants

## TL;DR

This paper investigates the significance of correcting for volume fluctuations in higher-order cumulant measurements, comparing the effectiveness of the Volume Fluctuation Correction (VFC) with traditional methods using toy models and UrQMD simulations.

## Contribution

It evaluates the validity of the VFC method under different models, highlighting its limitations beyond the independent particle production assumption.

## Key findings

- VFC performs well in toy models assuming IPP.
- VFC does not work effectively in UrQMD simulations.
- Residual volume fluctuation effects may persist after traditional corrections.

## Abstract

Initial volume fluctuation (VF) caused by participant fluctuation would be the background which should be subtracted from experimentally measured higher-order cumulants. STAR experiment has been applied Centrality Bin Width Correction (CBWC) to suppress VF. However, CBWC is not perfect method, there might be thus residual fractions of VF backgrounds. Recently, Volume Fluctuation Correction (VFC) was developed under the assumption of the independent particle production (IPP) model. In this talk, the importance of subtracting VF and validity of the VFC are studied by using simple toy models assuming IPP as well as UrQMD model. The results showed that VFC worked well in toy model but did not work well in UrQMD which imply that IPP model could be broken in UrQMD.