Pion, Kaon, and Proton Production in Central Pb-Pb Collisions at sqrt(sNN) = 2.76 TeV

Submission Date: 
09/08/2012
Article Information
Submission Form
System: 
Pb-Pb
Energy: 
2.76 TeV
Abstract Plain Text: 

In this Letter we report the first results on \pi^\pm, K^\pm, p and \pbar  production at mid-rapidity ($\left|y\right|<0.5$) in central \PbPb  collisions at \snn~=~2.76~TeV, measured by the ALICE experiment at  the LHC. The \pt\ distributions and yields are compared to  previous results at \snn~=~200~GeV and expectations from   hydrodynamic and thermal models.  The spectral shapes indicate a  strong increase of the radial flow velocity with \snn, which in  hydrodynamic models is expected as a consequence of the increasing  particle density. While the \kpi\ ratio is in line with predictions  from the thermal model, the \ppi\ ratio is found to be lower by a  factor of about 1.5. This deviation from thermal model  expectations is still to be understood.