Searching for the QCD Critical Point with Net-Proton Number Fluctuations

  • M. Szymański Institute of Theoretical Physics, University of Wroclaw
  • M. Bluhm Institute of Theoretical Physics, University of Wroclaw, SUBATECH UMR 6457 (IMT Atlantique, Universit´e de Nantes, IN2P3/CNRS), Extreme Matter Institute EMMI, GSI
  • K. Redlich Institute of Theoretical Physics, University of Wroclaw, Extreme Matter Institute EMMI, GSI
  • C. Sasaki Institute of Theoretical Physics, University of Wroclaw
Keywords: net-proton number fluctuations, QCD critical point, heavy-ion collisions

Abstract

Net-proton number fluctuations can be measured experimentally and, hence, provide a source of important information about the matter created during relativistic heavy ion collisions. Particularly, they may give us clues about the conjectured QCD critical point. In this work, the beam-energy dependence of ratios of the first four cumulants of the net-proton number is discussed. These quantities are calculated using a phenomenologically motivated model in which critical mode fluctuations couple to protons and antiprotons. Our model qualitatively captures both the monotonic behavior of the lowest-order ratio, as well as the non-monotonic behavior of higher-order ratios, as seen in the experimental data from the STAR Collaboration. We also discuss the dependence of our results on the coupling strength and the location of the critical point.

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Published
2019-09-18
How to Cite
Szymański, M., Bluhm, M., Redlich, K., & Sasaki, C. (2019). Searching for the QCD Critical Point with Net-Proton Number Fluctuations. Ukrainian Journal of Physics, 64(8), 766. https://doi.org/10.15407/ujpe64.8.766
Section
New Trends in High-Energy Physics (Conference materials)