Dynamical fluctuations of photon multiplicities in Pb ion interactions at 158 A GeV

Non-statistical fluctuations in the multiplicities of charged particles and photons and the total transverse energy in 158 A GeV Pb+Pb collisions are studied for a wide range of centralities. The centrality dependence of the charged particle multiplicity fluctuations in the measured data has been found to agree reasonably well with those obtained from a participant model. The motivation for studying relativistic heavy ion collisions is to gain understanding of equation of state of nuclear, hadronic and partonic matter commonly referred to as nuclear matter. Such a situation is quite suitable for the formation of a deconfined state of matter known as hot Quark-Gluon Plasma (QGP) which subsequently cools and expands. In this process the energy density becomes low enough so as a phase transition Quark-Gluon Plasma (QGP) to hadrons state occurs. (author)