What One Can Learn by Studying Spectator Remnants in Central Nucleus–Nucleus Collisions?
Tóm tắt
In central collisions of heavy relativistic nuclei spectator matter is represented by noninteracting nucleons from the nuclear periphery. In the context of the AAMCC model based on the Glauber Monte Carlo model to determine the volume of spectator matter and the models of the decay of excited spectator matter from the Geant4 toolkit, it is shown that the yields of a certain number of neutrons in central collisions of 208Pb nuclei are sensitive to the presence of the neutron skin. When the neutron skin is considered in the calculations using various parameterizations of the excitation energy of spectator matter, an increase in the yield of spectator neutrons is especially noticeable in the events without the emission of spectator protons. The proposed new method for studying the neutron skin in relativistic nucleus–nucleus collisions by means of zero degree calorimeters complements the known methods used at significantly lower collision energies. It can be implemented at existing experimental facilities.
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