Compression Effects in Relativistic Nucleus-Nucleus Collisions

Abstract
The negative pion multiplicity is measured for inelastic and central collisions of 40Ar with KCl at eight energies from 0.36 to 1.8 GeV/nucleon and for 4He and 40Ar on BaI2 at 977 and 772 MeV/nucleon, respectively. A systematic discrepancy in central collision data with a cascade model calculation which fits proton- and pion-nucleus cross sections but omits potential energy effects is used to derive the energy going into bulk compression of the system. A value of the compressibility constant of K = 240 MeV is extracted in a parabolic form of the nuclear matter equation of state.