If K is a finite simplicial complex and h is an injective map from the vertices of K to R, we show how to extend h to a discrete Morse function in the sense of Forman [Forman 02] in a reasonably efficient manner so that the resulting discrete Morse function mirrors the large-scale behavior of h. A concrete algorithm is given for the case where K is a subcomplex of R 3 .

K 0 S , Λ, Ξ, Ω and negative particle yields and transverse mass spectra have been measured at central rapidity in Pb-Pb and p-Pb collisions at 158 A GeV/c. Yields are studied as a function of the number of nucleons participating in the collision N part , which is estimated with the Glauber model. From p-Pb to Pb-Pb collisions the particle yields per participant increase substantially. The enhancement is more pronounced for multistrange particles, and exceeds an order of magnitude for the Ω. For a number of participants, N part , greater than 100, however, all yields per participant appear to be constant. To be published in Physics Letters B

A measurement of strange baryon and antibaryon production in Pb-Pb collisions has been carried out by the NA57 experiment at the CERN SPS, with 40 and 158 A GeV/c beam momentum. Results on Λ, Ξ and Ω hyperon yields at mid-rapidity in the most central 53% of Pb-Pb collisions at 40 A GeV/c are presented and compared with those obtained at higher energy, in the same collision centrality range.The Λ and Ξ − yields per unit rapidity stay roughly constant while those of Ω − , Λ, Ξ + and Ω + increase when going to the higher SPS energy. Hyperon yields at the SPS are compared with those from the STAR experiment in √ s N N = 130 GeVAu-Au collisions at RHIC.