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Title: Searching for minimum in dependence of squared speed-of-sound on collision energy

Experimental results of the rapidity distributions of negatively charged pions produced in proton-proton ( p - p ) and beryllium-beryllium (Be-Be) collisions at different beam momentums, measured by the NA61/SHINE Collaboration at the super proton synchrotron (SPS), are described by a revised (three-source) Landau hydrodynamic model. The squared speed-of-sound parameter c s 2 is then extracted from the width of rapidity distribution. There is a local minimum (knee point) which indicates a softest point in the equation of state (EoS) appearing at about 40 A  GeV/ c (or 8.8 GeV) in c s 2 excitation function (the dependence of c s 2 on incident beam momentum (or center-of-mass energy)). This knee point should be related to the searching for the onset of quark deconfinement and the critical point of quark-gluon plasma (QGP) phase transition.
ORCiD logo [1] ;  [1] ;  [2]
  1. Shanxi Univ., Taiyuan, Shanxi (China). Inst. of Theoretical Physics
  2. Stony Brook Univ. Stony Brook, NY (United States). Dept. of Chemistry & Physics
Publication Date:
Grant/Contract Number:
FG02-87ER40331; FG02-87ER40331.A008
Published Article
Journal Name:
Advances in High Energy Physics
Additional Journal Information:
Journal Volume: 2016; Journal ID: ISSN 1687-7357
Research Org:
New York State University Research Foundation
Sponsoring Org:
USDOE; National Natural Science Foundation of China (NNSFC)
Country of Publication:
United States
74 ATOMIC AND MOLECULAR PHYSICS; proton-proton collisions; pseudorapidity; diffusion; tev
OSTI Identifier:
Alternate Identifier(s):
OSTI ID: 1268266