Covariance Analysis of Symmetry Energy Observables from Heavy Ion Collision

Abstract

Using covariance analysis, we quantify the correlations between the interaction parameters in a transport model and the observables commonly used to extract information of the Equation of State of Asymmetric Nuclear Matter in experiments. By simulating ${}^{124}$Sn+${}^{124}$Sn, ${}^{124}$Sn+${}^{112}$Sn and ${}^{112}$Sn+${}^{112}$Sn reactions at beam energies of 50 and 120 MeV per nucleon, we have identified that the nucleon effective mass splitting are most strongly correlated to the neutrons and protons yield ratios with high kinetic energy from central collisions especially at high incident energy. The best observable to determine the slope of the symmetry energy, L, at saturation density is the isospin diffusion observable even though the correlation is not very strong ($\sim$0.7). Similar magnitude of correlation but opposite in sign exists for isospin diffusion and nucleon isoscalar effective mass. At 120 MeV/u, the effective mass splitting and the isoscalar effective mass also have opposite correlation for the double n/p and isoscaling p/p yield ratios. By combining data and simulations at different beam energies, it should be possible to place constraints on the slope of symmetry energy (L) and effective mass splitting with reasonable uncertainties.

13 pages, 1 figure

References in corpus (7)

• Constraints on the Symmetry Energy Using the Mass-Radius Relation of Neutron Stars
• Neutron and Proton Transverse Emission Ratio Measurements and the Density Dependence of the Asymmetry Term of the Nuclear Equation of State
• Higher-order effects on the incompressibility of isospin asymmetric nuclear matter
• Elliptic flow and system size dependence of transition energies at intermediate energies
• The influence of cluster emission and the symmetry energy on neutron-proton spectral double ratios
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• Black Holes with Intrinsic Spin

Cited by in corpus (15)

• Constraining the symmetry energy with heavy-ion collisions and Bayesian analyses
• Constraints on the symmetry energy and its associated parameters from nuclei to neutron stars
• Transport approaches for the Description of Intermediate-Energy Heavy-Ion Collisions
• Collision dynamics at medium and relativistic energies
• Progress of Quantum Molecular Dynamics model and its applications in Heavy Ion Collisions
• Connecting the nuclear EoS to the interplay between fusion and quasifission processes in low-energy nuclear reactions
• Isospin dynamics on neck fragmentation in isotopic nuclear reactions
• Impact parameter smearing effects on isospin sensitive observables in heavy ion collisions
• Examination of an isospin-dependent single-nucleon momentum distribution for the isospin-asymmetric nuclear matter in heavy-ion collisions
• Pre-equilibrium effects in charge-asymmetric low-energy reactions
• Constraining nucleon effective masses with flow and stopping observables from the S$\pi$RIT experiment
• Limiting symmetry energy elements from empirical evidence
• Beam energy dependence of the relativistic retardation effects of electrical fields on the ${\pi }^{-}/{\pi }^{+}$ ratio in heavy-ion collisions
• Isospin splitting of nucleon effective mass and symmetry energy in isotopic nuclear reactions
• On the spin-isospin decomposition of nuclear symmetry energy