1307.5543 (ALICE Collaboration)

Multi-strange baryon production at mid-rapidity in Pb-Pb collisions at
sqrt(s_NN) = 2.76 TeV    [PDF]

ALICE Collaboration

The ALICE experiment at the LHC has measured the production of {\Xi}- and {\Omega}- baryons and their anti-particles in Pb-Pb collisions at sqrt(s_NN) = 2.76 TeV. The transverse momentum spectra at mid-rapidity (|y| < 0.5) for charged {\Xi} and {\Omega} hyperons have been studied in the range 0.6 < pT < 8.0 GeV/c and 1.2 < pT < 7.0 GeV/c, respectively, and in several centrality intervals (from the most central 0-10% to the most peripheral 60-80% collisions). These spectra have been compared with the predictions of recent hydrodynamic models. In particular, the Krak{\'o}w and EPOS models give a satisfactory description of the data, with the latter covering a wider pT range. Mid-rapidity yields, integrated over pT, have been determined. The hyperon-to-pion ratios are similar to those at RHIC: they rise smoothly with centrality up to ~ 150 and saturate thereafter. The enhancements (yields per participant nucleon relative to p-p collisions) increase both with the strangeness content of the baryon and with centrality, but are less pronounced than at lower energies.

View original: http://arxiv.org/abs/1307.5543