| Full text | |
| Author(s): |
Giannini, Andre, V
;
Grassi, Frederique
;
Luzum, Matthew
Total Authors: 3
|
| Document type: | Journal article |
| Source: | PHYSICAL REVIEW C; v. 100, n. 1, p. 10-pg., 2019-07-31. |
| Abstract | |
Starting from a color glass condensate (CGC) framework, based on a running-coupling improved k T -factorized formula, we calculate bulk observables in several heavy-ion collision systems. This is done in two ways: first we calculate the particle distribution directly implied from the CGC model, and we compare this to the case where it is instead used as the initial condition for a hybrid hydrodynamic simulation. In this way, we can assess the effects of hydrodynamic and hadronic evolution by quantifying how much they change the results from a pure initial state approach and, therefore, to what extent initial condition models can be directly compared to experimental data. We find that entropy production in subsequent hydrodynamic evolution can increase multiplicity by as much as 50%. However, disregarding a single overall normalization factor, the centrality, energy, and system size dependencies of charged hadron multiplicity are only affected at the similar to 5% level. Because of this, the parameter-free prediction for these dependencies gives reasonable agreement with experimental data whether or not hydrodynamic evolution is included. On the other hand, our model results are not compatible with the hypothesis that hydrodynamic evolution is present in large systems, but not in small systems like p-Pb, in which case the dependence of multiplicity on system size would be stronger than seen experimentally. Moreover, we find that hydrodynamic evolution significantly changes the distribution of momentum, so that observables such as the mean transverse momentum are very different from the initial particle production and much closer to measured data. Finally, we find that a good agreement to anisotropic flow data cannot be achieved due to the large eccentricity generated by this model. (AU) | |
| FAPESP's process: | 17/14974-8 - Phenomenology of relativistic heavy-ion collisions: QCD under extreme conditions |
| Grantee: | André Veiga Giannini |
| Support Opportunities: | Scholarships in Brazil - Post-Doctoral |
| FAPESP's process: | 18/23677-0 - Early-time dynamics of hadronic collisions beyond the Gaussian approximation of the Color Glass Condensate |
| Grantee: | André Veiga Giannini |
| Support Opportunities: | Scholarships abroad - Research Internship - Post-doctor |
| FAPESP's process: | 16/24029-6 - Investigating the strong nuclear interactions under extreme conditions |
| Grantee: | Matthew William Luzum |
| Support Opportunities: | Research Grants - Young Investigators Grants |
| FAPESP's process: | 17/05685-2 - Hadronic physics in high energy nuclear collisions |
| Grantee: | Jun Takahashi |
| Support Opportunities: | Special Projects |