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arXiv · 1408.0761

Understanding the $p/π$ ratio at LHC due to QCD mass spectrum

Jacquelyn Noronha-Hostler·Carsten Greiner
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Abstract

Thermal fits have consistently reproduced the experimental particles yields of heavy ion collisions, however, the proton to pion ratio from ALICE Pb+Pb $\sqrt{s_{NN}}=2.76$ TeV is over-predicted by thermal models- known at the $p/π$ puzzle. Here we test the relevance of the extended mass spectrum, i.e., include Hagedorn states (resonances that follow an exponential mass spectrum and have very short life times) on the $p/π$ puzzle. We find that the extended mass spectrum is able to reproduce particle ratios at both RHIC and the LHC as well as being able to match the lower $p/π$ ratio at the LHC through dynamical chemical equilibration.

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Jacquelyn Noronha-Hostler, Carsten Greiner. 2014-08-04. Understanding the $p/π$ ratio at LHC due to QCD mass spectrum. https://doi.org/10.1016/j.nuclphysa.2014.08.101

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