The influence of Pauli blocking on the deducing of the in-medium nucleon-nucleon elastic cross section

The comparison of microscopic transport model simulations with heavy-ion collision experimental data is one of the main approaches to extracting information on the nuclear equation of state (EoS). The nucleon-nucleon elastic cross-section in the medium, as a crucial input of transport models, has a significant impact on simulating the heavy-ion collision process and extracting EoS information. However, due to the complexity of nuclear forces and many-body problems, our knowledge about the nucleon-nucleon elastic cross-section in the medium is still limited.In this paper, based on the ultra-relativistic quantum molecular dynamics model, we study the effects of different Pauli blocking treatments and the in-medium nucleon-nucleon elastic cross section on various observables, such as direct flow, elliptic flow, average transverse momentum, and nuclear stopping power, in ^197mathrmAu+^197mathrmAucollisions at incident energies of 0.1A and 0.15A GeV.Our results show that the elliptic flow and nuclear stopping power in the midrapidity region are sensitive to the Pauli blocking and the in-medium nucleon-nucleon elastic cross-section, and exhibits a clear dependence on impact parameters.Moreover, the average transverse momentum of protons in the projectile-target rapidity region is highly sensitive to the effect of Pauli blocking, and the average transverse momentum of protons in the midrapidity region is influenced by both effects.These findings suggest that multiple observables under varying impact parameters are required to simultaneously constrain the Pauli blocking treatment and the in-medium nucleon-nucleon elastic cross-section.