EUROPEAN JOURNAL OF PHYSICS, cilt.24, sa.4, ss.341-349, 2003 (SCI-Expanded)
We study the evolution of matter produced after the collision of two heavy nuclei at high energy. The matter produced may pass from the hadron phase into a new state of matter called quark-gluon plasma (QGP). The aim of this paper is to discuss how a new state of matter can be observed. Whilst matter is in the QGP phase, particles that arise from the interactions between the constituents of the plasma provide information concerning the state of the plasma.