Squeeze-out of nuclear matter in peripheral heavy-ion collisions and momentum-dependent effective interactions - art. no. 064611

We perform a systematic study of in-plane and out-of-plane proton and neutr on how from nucleus-nucleus collisions within the Boltzmann-Uehling-Uhlenbe ck transport approach, employing different parameter sets for the mean-fiel d potentials that can be characterized by the nuclear incompressibility and the stiffness of the momentum-dependent potential. We find that a simultan eous description of the experimental data from the BEVALAC and the SIS on b oth the nucleon squeeze-out nu (2) and the in-plane flow F at beam energies E-lab = 0.15-2 A GeV requires a mean field with strong momentum dependence , i.e., an effective Landau mass m* = 0.68m(0) at normal nuclear matter den sity rho (0)=0.17 fm(-3), where m(0)=0.938 GeV is the bare nucleon mass. So me experimental data on the squeeze-out require an even stiffer momentum de pendence (m* approximate to 0.62m(0)). All systems investigated are found t o be compatible with m*/m(0) = 0.65 +/- 0.03.