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Baryon stopping as a signal of the mixed phase onset

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 نشر من قبل Yuri B. Ivanov
 تاريخ النشر 2011
  مجال البحث
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 تأليف Yu.B. Ivanov




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It is argued that the experimentally observed baryon stopping indicates a non-monotonous behaviour as a function of the incident energy of colliding nuclei. This can be quantified by a midrapidity reduced curvature of the net-proton rapidity spectrum and reveals itself as a zigzag irregularity in the excitation function of this curvature. The three-fluid dynamic calculations with a hadronic equation of state (EoS) fail to reproduce this irregularity. At the same time, the same calculations with an EoS involving a first-order phase transition and a crossover one into the quark-gluon phase do reproduce this zigzag behaviour, however only qualitatively.



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192 - Yu.B. Ivanov 2010
It is argued that the experimentally observed baryon stopping may indicate (within the present experimental uncertainties) a non-monotonous behaviour as a function of the incident energy of colliding nuclei. This can be quantified by a midrapidity re duced curvature of the net-proton rapidity spectrum. The above non-monotonous behaviour reveals itself as a zig-zag irregularity in the excitation function of this curvature. The three-fluid dynamic calculations with a hadronic equation of state (EoS) fail to reproduce this irregularity. At the same time, the same calculations with an EoS involving a first-order phase transition into the quark-gluon phase do reproduce this zig-zag behaviour, however only qualitatively.
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