# Latest results from the EbyE NLO EKRT model

## TL;DR

This paper reviews the EbyE NLO EKRT model's ability to describe heavy-ion collision data from LHC and RHIC, constraining QCD matter properties and testing initial state calculations through comprehensive analysis of various observables.

## Contribution

It provides a systematic analysis of the EbyE NLO EKRT model's performance across multiple observables and energies, refining the understanding of QCD matter properties and initial conditions.

## Key findings

- Model matches well with LHC and RHIC data
- Predictions for 5.02 TeV LHC align with measurements
- Constraints on shear viscosity-to-entropy ratio eta/s(T)

## Abstract

We review the results from the event-by-event next-to-leading order perturbative QCD + saturation + viscous hydrodynamics (EbyE NLO EKRT) model. With a simultaneous analysis of LHC and RHIC bulk observables we systematically constrain the QCD matter shear viscosity-to-entropy ratio eta/s(T), and test the initial state computation. In particular, we study the centrality dependences of hadronic multiplicities, pT spectra, flow coefficients, relative elliptic flow fluctuations, and various flow-correlations in 2.76 and 5.02 TeV Pb+Pb collisions at the LHC and 200 GeV Au+Au collisions at RHIC. Overall, our results match remarkably well with the LHC and RHIC measurements, and predictions for the 5.02 TeV LHC run are in an excellent agreement with the data. We probe the applicability of hydrodynamics via the average Knudsen numbers in the space-time evolution of the system and viscous corrections on the freeze-out surface.