Received 12 April 2017; revised 20 June 2017; accepted 20
September 2017
One of the physics goals of the NA61/SHINE
collaboration at the CERN Super Proton Synchrotron is to study
the phase diagram of hadronic matter. To this end, a series of
heavy ion collision measurements are performed. It is believed
that above a certain collision energy and system size a phase
transition between the hadronic matter and quark–gluon plasma
occurs. A number of observables have been developed to
determine which of the phases was created at the early stage
of the collision. This report discusses the dependence of the
ratio of the mean number of produced pions to the mean number
of wounded nucleons on the Fermi energy measure. For
comparison with other measurements this is often presented in
the form of the “kink” plot. This plot is presented enriched
with preliminary results for 40Ar+45Sc
central collisions at 13A, 19A, 30A, 40A,
75A and 150A GeV/c beam momenta. The
results are finally compared to data from other experiments.
Keywords: NA61/SHINE,
CERN, quark–gluon plasma, onset of deconfinement
PACS: 25.75.-q,
25.75.Nq
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