Investigation Of Heavy Ion Reaction At Low And Medium Energy Through Nuclear Stopping

Using an antisymmetrized molecular dynamics model (AMD), the data of kinematical-1y complete events are compared with the experimental INDRA data through nuclear stopping in Xe+Sn collisions at10-100A MeV. The full complete stopping is ob-served in the AMD calculations whereas the experimental data show a decrease from the complete stopping in the energy range of10-25A MeV. In the range of25-50A MeV, a sharp decrease is observed in the AMD simulations and reaches a similar value to the experimental one at50A MeV. Above50A MeV, a flattening of nuclear stopping is obtained, indicating a transition from the competition between the Pauli-blocking and the nucleon-nucleon (NN) collisions to the NN collision dominant mechanism. The sensitivity of the nuclear stopping is studied through interactions with different EOSs (soft and stiff) and in-medium NN cross sections in different energy domain. Above25A MeV, both EOS and different NN cross sections can affect the nuclear stopping, but none of these parameters used in AMD model can reproduce the experi-mental data at20-30A MeV. On the other hand, below25A MeV, nuclear stopping is not sensitive to both of the EOSs and the NN cross sections because of the complete nuclear stopping. This indicates that some important mechanisms may be missing in AMD or that the selection of central collision events may be significantly differen-t between the experiments and the simulations in this energy range, but the latter is probably not the decisive difference source based on the current result.