Quark-gluon plasma fireball explosion

We identify the major physics milestones in the development of strange hadr ons as an observable for both the formation of a quark-gluon plasma (QGP), and of the ensuing explosive disintegration of a deconfined matter fireball formed in relativistic heavy-ion collisions at 160-20 A GeV. We describe t he physical properties of the QGP phase and show agreement with the expecta tions based on an analysis of hadron abundances. We then also demonstrate t hat the I nl shape of hadron spectra is in qualitative agreement with the s udden breakup of a supercooled QGP fireball.