Abstract
In this Letter we report the first results on , , , and production at midrapidity () in central Pb-Pb collisions at , measured by the ALICE experiment at the LHC. The distributions and yields are compared to previous results at and expectations from hydrodynamic and thermal models. The spectral shapes indicate a strong increase of the radial flow velocity with , which in hydrodynamic models is expected as a consequence of the increasing particle density. While the ratio is in line with predictions from the thermal model, the ratio is found to be lower by a factor of about 1.5. This deviation from thermal model expectations is still to be understood.
- Received 14 August 2012
DOI:https://doi.org/10.1103/PhysRevLett.109.252301
This article is available under the terms of the Creative Commons Attribution 3.0 License. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI.
© 2012 CERN, for the ALICE Collaboration