Measurement Of

Introduction A new state of matter, called Quark Gluon Plasma(QGP) may be formed in ultra-relativistic heavy ion collision if sufficient high energy density is reached. Transverse momentum distribution of the produced particles is one of the possible signatures of QGP. For a thermalised system undergoing phase transition, the mean transverse momentum hp T i of the produced particles varies with multiplicity like the temperature with the entropy density, it first increases below the transition, then saturates in the transition region and increases again above the transition region. Usually inclusive pT -spectra of produced particles are measured and hp T i is derived as a function of rapidity density [1]. The WA80 Collaboration also reported such measurement for photons and ß 0 's [2] in 16 O induced reactions. The hp T<F3