Conserved charge fluctuations with HISQ fermions
arXiv:1301.6526
Abstract
We calculate cumulants of fluctuations of net-baryon number, net-electric charge and net-strangeness, in the framework of lattice regularized QCD. We use a highly improved staggered quark (HISQ) action on lattices with temporal extent of N_tau=6,8 and 12 and almost physical quark masses. By means of a Taylor expansion in various chemical potentials and under demanding both strangeness neutrality as well as the correct isospin asymmetry, we evaluate these fluctuations at conditions met in heavy ion collisions. Cumulants of net-electric charge fluctuations can, in principle, also be measured in heavy ion experiments. We therefore propose a method to extract freeze-out parameters, such as the freeze-out temperature and baryon chemical potential, based on a comparison of lattice results and experimental measurements of two different ratios of net-electric charge cumulants. As this method involves only (lattice) QCD results and experimental measurements it is model independent and, for the purpose of extracting freeze-out parameters, does not require any input from hadron resonance gas model calculations.
arXiv comment8 pages, 4 figures, talk presented at the Xth Quark Confinement and the Hadron Spectrum, October 8-12, 2012, TUM Campus Garching, Munich, Germany
References in corpus (9)
- The chiral and deconfinement aspects of the QCD transition
- Fluctuations and Correlations of net baryon number, electric charge, and strangeness: A comparison of lattice QCD results with the hadron resonance gas model
- Freeze-out Conditions in Heavy Ion Collisions from QCD Thermodynamics
- Baryon number conservation and the cumulants of the net proton distribution
- The RHIC Beam Energy Scan Program: Results from the PHENIX Experiment
- Search for the QCD Critical Point by Higher Moments of Net-proton Multiplicity Distributions at STAR
- Baryon number and charge fluctuations from lattice QCD
- QCD bulk thermodynamics and conserved charge fluctuations with HISQ fermions
- Freeze-out Conditions from Lattice QCD