Importance of separated efficiencies between positively and negatively charged particles for cumulant calculations

TL;DR

This paper demonstrates that using separated efficiency corrections for positive and negative particles significantly impacts cumulant calculations in heavy-ion collision experiments, affecting the interpretation of net-proton fluctuation results.

Contribution

It highlights the necessity of applying separated efficiency corrections in cumulant analyses, providing both Monte Carlo and analytical evidence for their importance.

Findings

Sσ in STAR net-proton results is suppressed by 5-10% in central collisions.

Suppression increases to 10-20% in peripheral collisions.

Separated efficiencies significantly influence fluctuation measurements.

Abstract

We show the importance of separated efficiency corrections between positively and negatively charged particles for cumulant calculations by Monte Carlo toy models and analytical calculations. Our results indicate that S{\sigma} in published net-proton results from the STAR experiment will be suppressed about 5 to 10% in central collisions, and 10 to 20% in peripheral collisions at the beam energy of \sqrt s_{NN} = 62.4 and 200 GeV if the separated efficiencies are used to efficiency correction.