# Quark number fluctuations at high temperatures

## TL;DR

This paper computes high-order quark number fluctuations in high-temperature QCD using lattice simulations, comparing results with theoretical models and analyzing flavor correlations.

## Contribution

It provides detailed lattice calculations of quark number fluctuations up to sixth order for multiple quark flavors at high temperatures, including comparisons with models.

## Key findings

- Fluctuations approach ideal gas limits at high temperatures.
- Results agree with quasi-particle and perturbative models.
- Flavor correlations show significant insights into quark interactions.

## Abstract

We calculate the second, fourth and sixth order quark number fluctuations in the deconfined phase of 2+1 flavor QCD using lattices with temporal extent Nt=4, 6, 8 and 12. We consider light, strange and charm quarks. We use p4 action for valence quarks and gauge configurations generated with p4 action with physical value of the strange quark mass and light quark mass mq=0.1ms generated by the RBC-Bielefeld collaboration. We observe that for all quark masses the quark number fluctuations rapidly get close to the corresponding ideal gas limits. We compare our results to predictions of a quasi-particle model and resummed high temperature perturbative calculations. We also investigate correlations among different flavor channels.