A Study Of Shannon Information Entropy In Fregment Cross Section In Projectile Fragmentation Reactions Based On Modified Statistical Abrasion-ablation Model

The new generation of radioactive nuclear beam facilities will provide new opportunities to explore the extreme nuclei.There are many new phenomena in nuclide near the neutron drop line compared those at the?-stable line,which always form exotic neutron skin or halo structure.There are many methods to determine the neutron skin thickness in experiments,but most of them depend on the model and causes obvious experimental phenomena and errors.The dynamical properties of heavy ion collisions make it difficult and complex to study nuclear matter and its evolution.Shannon information entropy theory provides a new method and observation to understand physical phenomena theoretically and experimentally.Therefore,it is of great significance in nuclear physics to measure neutron skin thickness by using configurational information entropy,and to explore the scaling phenomenon of uncertainty in Shannon information entropy,the isobaric yield ratio for mirror nuclei of projectile nucleus and the isotope effect produced in projectile fragmentation.The main content of this thesis has been divided into four parts:the density distribution and cross-section distribution data of fragmentation reaction product of 350 Me V/u ^40-60Ca+~9Be and ⁴⁸Ca+~9Be with different f_n reactions are measured by using the improved statistical abrasion–ablation model;(1)the correlation between the density distribution or cross-section distribution and neutron skin thickness is studied by using the configurational information entropy method.The results show that there is a linear relationship between configurational information entropy and neutron skin thickness,which can be used to predict neutron skin thickness well;(2)using the isobaric yield ratio for mirror nuclei,the symmetry energy of fragments in heavy ion collisions at finite temperature can be studied to explore the isobaric yield ratio for mirror nuclei in different systems,and the dependence between neutron skin effect and the isobaric yield ratio for mirror nuclei of mirror nuclei can be obtained;(3)based on the fragment of nuclear matter in heavy ion collisions will carry part of the information of the system,by using the probe of information uncertainty independent of the system,we can observe the scaling phenomenon in the ⁴⁸Ca/⁴⁰Ca reaction fragment,and explain the scaling phenomenon;(4)by using 350 Me V/u ^40,48,54,60Ca+~9Be,the results show that with the increase of reaction degree,the isospin effect decreases,and the isospin effect of cross-section distribution of central reaction products also disappears.