Particle spectra in Pb-Pb collisions at $\sqrt{{\mathbf{s}}_{\mathbf{NN}}}=\mathbf{2}.\mathbf{76}$ TeV

Particle production in Pb-Pb collisions at $\sqrt{s_{NN}}=2.76$ TeV is studied in the $(3+1)$-dimensional viscous hydrodynamic model. The shapes of the calculated transverse momentum spectra of ${\pi }^{+}$, $K^{+}$, protons, ${\Xi }^{-}$, and ${\Omega }^{-}$ are in satisfactory agreement with preliminary data of the ALICE Collaboration, while the particle ratio $p/{\pi }^{+}$ is slightly overpredicted, and the strange baryon yields are underpredicted.

Figure 1

Charged-particle distributions in pseudrapidity in Pb-Pb collisions at ${\sqrt{s}}_{NN}=2.76$ TeV, for centralities (from top to bottom) 0%–5%, 5%–10%, 10%–20%, ..., 50%–60%. Results from viscous hydrodynamics (lines) are compared to preliminary data of the ALICE Collaboration (symbols) [3].

Figure 2

Transverse momentum spectra of ${\pi }^{+}$, $K^{+}$, and $p$ (from top to bottom) in Pb-Pb collisions with centralities 0%–5%, obtained in the viscous hydrodynamic model with $\zeta /s=0.04$ and $T_f=150$ MeV (dashed lines), $\zeta /s=0.04$ and $T_f=140$ MeV (dotted lines), and $\zeta /s=0.08$ and $T_f=140$ MeV (solid lines). Symbols represent preliminary data of the ALICE Collaboration [3]. The dashed-dotted line represents the result of the viscous hydrodynamic calculation with $\zeta /s=0.08$ and $T_f=140$ MeV but without bulk viscosity corrections at freeze-out.

Figure 3

Interferometry radii in Pb-Pb collisions with centralities 0%–5% as functions of the pion pair momentum, obtained in the viscous hydrodynamic model with $\zeta /s=0.04$ and $T_f=150$ MeV (dashed lines), $\zeta /s=0.04$ and $T_f=140$ MeV (dotted line), and $\zeta /s=0.08$ and $T_f=140$ MeV (solid lines). Symbols represent preliminary data of the ALICE Collaboration [2].

Figure 4

Transverse momentum spectra of ${\pi }^{+}$, $K^{+}$, and $p$ (from to to bottom) in Pb-Pb collisions with centralities 10%–20% (a) and 30%–40% (b), obtained in the viscous hydrodynamic model (solid lines). Symbols represent preliminary data of the ALICE Collaboration [3].

Figure 5

Transverse momentum spectra of ${\Lambda }^0$ (dashed line), ${\Xi }^{-}$ (dotted line and stars), and ${\Omega }^{-}$ (solid line and diamonds) in Pb-Pb collisions with centralities 0%–20% (a) and 20%–40% (b). The lines and the symbols represent the results of the viscous hydrodynamic model and the preliminary data of the ALICE Collaboration [16] respectively.

Figure 6

Ratios of particle yields in Pb-Pb collisions with centralities 0%–20%; preliminary data of the ALICE Collaboration (squares) [16] are compared to results of viscous hydrodynamic calculations (lines).

Figure 7

Rapidity distributions of ${\pi }^{+}$ (solid line), $K^{+}$ (dashed line), and $p$ (dotted line) emitted in Pb-Pb collisions with centralities 0%–5%, calculated in the (3+1)-D viscous hydrodynamic model.

Figure 8

Elliptic flow coefficient of charged particles as function of transverse momentum for three centrality classes calculated in the viscous hydrodynamic model (lines); the symbols represent the experimental results of the ALICE Collaboration [46].

Figure 9

Elliptic flow coefficient of identified particles as function of transverse momentum calculated in the viscous hydrodynamic model (lines); the symbols represent the preliminary results of the ALICE Collaboration [47], centrality 40%–50%.