Multi-strange baryon production in Pb-Pb and pp collisions at $\sqrt{s_{NN}}$ = 2.76 TeV with the ALICE experiment at the LHC

The production of $\Xi^{-}$ and $\Omega^{-}$ baryons and their anti-particles in Pb-Pb and pp collisions at $\sqrt{s_{NN}}$ = 2.76 TeV has been measured by the ALICE collaboration. The transverse momentum spectra at mid-rapidity (|y| < 0.5) in pp and Pb-Pb collisions for five centrality intervals have been compared with model predictions. Hyperon yields and spectra in Pb-Pb collisions, normalized to the corresponding measurements in pp at the same centre-of-mass energy, allow the study of the strangeness enhancement and the nuclear modification factor as a function of the transverse momentum ($p_{T}$) and collision centrality.