On the K±-meson production from the quark-gluon plasma phase in ultra-relativistic heavy-ion collisions

An abundance of the strangeness that can be induced in thermalized quark-gluon plasma (QGP) is considered as a signal of the QGP phase appearing in the intermediate state of ultra-relativistic heavy-ion collisions. As a quantitative characteristic of this signal, we take the ratio RK+K = NK+/N-K of the multiplicities of the production of K+/- mesons. This ratio is evaluated for K mesons produced from thermalized QGP phase and also for K mesons produced by the quark-gluon system out of the QGP phase. For a thermalized QGP phase, the ratio RK+K has been found a smooth function of a 3-momentum of the K+/- meson and in the region 160 MeV < T< 200 MeV. We show that at T = 175 MeV our prediction for the ratio RK+K (q, T = 175) = 180(0.180)(+0.04) agrees well with the experimental data of NA49 and NA44 collaborations on central ultra-relativistic Pb+Pb collisions at 158 GeV/A, R-K+K(exp) =1.80 +/- 0.10. For the K+ and pi(+) multiplicities we have obtained the value RK+pi+(q, T = 175) = 0.134 +/- 0.014 agreeing well with the experimental value R-K+pi+(exp) =0.137 +/- 0.008 obtained by NA35 collaboration in the nucleus-nucleus collisions at 200 GeV/A.