Abnormally small yield of baryons and antibaryons as signal of quark-gluon plasma formation

It is well known that the spectrum of protons and leptons is a meaningful signal of quark-gluon plasma formation because photons and leptons leave the plasma volume without interaction. Because of the confinement of quarks and gluons, with the hadron spectrum the situation is more complex. The present theory, unfortunately, does not allow to solve this problem using only the basic principle of the theory. This is why the hadron spectrum has to be calculated within the framework of some model. The use of the chromoelectric flux tube model is described. The radiation pressure was shown to be small and therefore the used approximation of a one-dimensional hydrodynamic expansion of plasma was legitimate. The tube formed between the quark and the plasma was supposed to be tightened in the shortest way (a minimum of energy) and with masses of u,d-quarks equal to zero. (Z.S.) 5 refs