Correlations of Mass-shifted Bosons

If hadronic mass-shifts in medium are accompanied with a sudden freeze-out, they were shown to result in squeezing of the fields 1,2 and as a consequence, new kind of back-to-back correlations of the observed quanta may appear . The theoretical description of these back-to-back correlations were given first for static sources in refs., however, the results were limited for those particles that are their own anti-particles, like the φ-s or π-s. The description of backto-back correlations was generalized recently to particle anti-particle pairs in refs. 4,5 and in ref. . In the present contribution we discuss these new kind of back-to-back correlations following the lines of ref. . We assume the validity of relativistic hydrodynamics up to freezeout. The local temperature field T (x), the chemical potential distribution μ(x), the four-velocity distribution u(x) and the oriented volume elements on freeze-out hypersurface dΣ(x) are given on the freeze-out hypersurface Σ, the space-time points are denoted by x = (t, r). The temperature, flow and chemical potential distributions can be taken from realistic hydrodynamical calculations, for example, from refs..