Nuclear Fragments in 12C + 9Be Interactions at an Energy of 2 GeV per Nucleon

Differential cross sections for the production of nuclear fragments at an angle of 3.5° in the fragmentation of 2-GeV/nucleon carbon ions on a beryllium target were measured in the FRAGM experiment performed at the ITEP-TWA heavy-ion accelerator-accumulator complex. The predictions of four Monte Carlo models of ion-ion interactions (BC, INCL, LAQGSM, and QMD) were tested on the basis of a comparison with the momentum spectra of fragments. Successes and drawbacks of these models are discussed. The energy spectra of protons and 3He nuclei in the cumulative region in the projectile rest frame are well described by an exponential dependence, which make it possible to estimate temperature parameters of their emission source.