In search of quark matter — The new round of tests

Heavy ion collisions at very high energy offer conditions such that a quark gluon plasma could be formed. Specific signals are used to probe what is actually happening. The first round of tests, with small to medium size ions, is now completed. New rounds of tests using the heaviest ions and, later on, much higher energies, will take place over the coming years. The present situation is assessed with a look at the information which the new round of tests should bring.