ar X iv : 0 80 5 . 15 87 v 1 [ he p - ph ] 1 2 M ay 2 00 8 ” Latent heat ” of first - order varying pressure transitions

We consider the energy release associated with first-order transition by Gibbs construction. Universal formulae for the energy release from one homogeneous phase to the other is given. We find the energy release per a converted particle varies with number density. As an example, the deconfinement phase transition at supranuclear densities is discussed in detail. The mean energy release per a converted baryon is of order 0.1MeV, much smaller than the energy release of phase transition by Mexwell construction, in RMF theory description for hadronic matter and MIT bag description for quark matter for a wider parameter region. PACS numbers: 97.60.Jd, 05.70.Fh, 12.38.Mh, 64.60.-i