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Measurements of Neutrons in 11.5 A GeV/c Au+Pb Heavy Ion Collisions

E864 Collaboration·T. A. Armstrong
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Abstract

We present measurements from Brookhaven Experiment 864 of neutron invariant multiplicity in 11.5 A GeV/c Au+Pb collisions. The measurements span a rapidity range from center-of-mass to beam rapidity (y(beam)=3.2) and are presented as a function of event centrality. The results are compared with E864 measurements of proton invariant multiplicity and an average n/p ratio at hadronic freeze-out of 1.19+-.08 is determined for the rapidity range y=1.6 to y=2.4. We discuss briefly the implications of this ratio within a simple equilibrium model of the collision system.

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E864 Collaboration, T. A. Armstrong. 1999-09-02. Measurements of Neutrons in 11.5 A GeV/c Au+Pb Heavy Ion Collisions. https://doi.org/10.1103/physrevc.60.064903

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