Heavy Residue Isoscaling as a Probe of the Process of N/Z Equilibration

Abstract

The isotopic and isobaric scaling behavior of the yield ratios of heavy projectile residues from the collisions of 25 MeV/nucleon 86Kr projectiles on 124Sn and 112Sn targets is investigated and shown to provide information on the process of N/Z equilibration occurring between the projectile and the target. The logarithmic slopes $\alpha$ and ${\beta }^{{}^{\prime }}$ of the residue yield ratios with respect to residue neutron number N and neutron excess N--Z are obtained as a function of the atomic number Z and mass number A, respectively, whereas excitation energies are deduced from velocities. The relation of the isoscaling parameters $\alpha$ and ${\beta }^{{}^{\prime }}$ with the N/Z of the primary (excited) projectile fragments is employed to gain access to the degree of N/Z equilibration prior to fragmentation as a function of excitation energy. A monotonic relation between the N/Z difference of fragmenting quasiprojectiles and their excitation energy is obtained indicating that N/Z equilibrium is approached at the highest observed excitation energies. Simulations with a deep-inelastic transfer model are in overall agreement with the isoscaling conclusions. The present residue isoscaling approach to N/Z equilibration offers an attractive tool of isospin and reaction dynamics studies in collisions involving beams of stable or rare isotopes.

arXiv comment15 pages, 4 figures, submitted to Phys. Lett. B

References in corpus (15)

• Isospin Physics in Heavy-Ion Collisions at Intermediate Energies
• Isotopic Scaling in Nuclear Reactions
• Caloric curves and critical behavior in nuclei
• Isoscaling in Light-Ion Induced Reactions and its Statistical Interpretation
• Isospin-tracing: A probe of non-equilibrium in central heavy-ion collisions
• Nuclear Isospin Diffusivity
• Isotopic Scaling of Heavy Projectile Residues from the collisions of 25 MeV/nucleon 86Kr with 124Sn, 112Sn and 64Ni, 58Ni
• Compatibility of localized wave packets and unrestricted single particle dynamics for cluster formation in nuclear collisions
• Isospin non-equilibrium in heavy-ion collisions at intermediate energies
• Enhanced Production of Neutron-Rich Rare Isotopes in the Reaction of 25 MeV/nucleon Kr-86 on Ni-64
• Conditions for Isoscaling in Nuclear Reactions
• Effect of nucleon exchange on projectile multifragmentation in the reactions of 28Si + 112Sn and 124Sn at 30 and 50 MeV/nucleon
• Influence of a momentum dependent interaction on the isospin dependence of fragmentation and dissipation in intermediate energy heavy ion collisions
• Heavy Residues with A<90 in the Asymmetric Reaction of 20 AMeV 124Sn+27Al as a Sensitive Probe of the Onset of Multifragmentation
• Isospin relaxation time in heavy-ion collisions at intermediate energies

Cited by in corpus (17)

• Reaction Dynamics with Exotic Beams
• Experimental determination of the symmetry energy of a low density nuclear gas
• Probing the Nuclear Symmetry Energy with Heavy Ion Collisions
• Probing the density dependence of the symmetry potential with peripheral heavy-ion collisions
• Heavy Residue Isoscaling as a Probe of the Symmetry Energy of Hot Fragments
• Projectile fragmentation reactions and production of nuclei near the neutron drip-line
• Isospin Dynamics in Peripheral Heavy Ion Collisions at Fermi Energies
• Tracing the evolution of the symmetry energy of hot nuclear fragments from the compound nucleus towards multifragmentation
• Constraining the Symmetry Term in the Nuclear Equation of State at Sub-Saturation Densities and Finite Temperatures
• Isospin transport in 84Kr + 112,124Sn collisions at Fermi energies
• IMF isotopic properties in semi-peripheral collisions at Fermi energies
• Effect of nuclear periphery on nucleon transfer in peripheral collisions
• Effect of neutron skin thickness on projectile fragmentation
• Experimental determination of the quasi-projectile mass with measured neutrons
• Experimental study of the ${}^{40,48}$Ca+ ${}^{40,48}$Ca reactions at 35 MeV/nucleon
• Dynamical aspects of isotopic scaling
• Study of quasi-projectile properties at Fermi energies in 48Ca projectile systems