Triple high energy nuclear and hadron collisions - a new method to study QCD phase diagram at high baryonic densities

Abstract

We propose an entirely new method to study the phase diagram of strongly interacting matter by means of scattering the two colliding beams at the fixed target. Here we present the results of simulations of the most central triple nuclear collisions with the UrQMD 3.4 model for the beam center-of-mass collision energies $$\sqrt{s_{NN}} = 2.76\ \hbox {TeV}$$ s NN = 2.76 TeV and $$\sqrt{s_{NN}} = 200\ \hbox {GeV}$$ s NN = 200 GeV . The main outcome of our modeling is that even at these very high collision energies the initial baryonic charge densities are about 3 times higher than the ones achieved in the ordinary binary nuclear collisions. As a result, for instance, the yields of protons and $$\varLambda $$ Λ -hyperons are strongly enhanced in the triple nuclear collisions. The other prospective applications of this method are briefly discussed. Among them we consider the low energy collisions of three nuclei of lead, passing through an intermediate system with an electric charge of 246 units which exceeds essentially the critical value of 173 and, hence, this may be of crucial importance to study the spontaneous emission of positron-electron pairs from the vacuum. We present the convincing arguments that the triple nuclear collisions method will allow the high energy nuclear physics community to create a new frontier in the studies of the QCD phase diagram and to lift up these studies to an entirely new level.