Isospin dependent multifragmentation of relativistic projectiles

Abstract

The N/Z dependence of projectile fragmentation at relativistic energies has been studied with the ALADIN forward spectrometer at the GSI Schwerionen Synchrotron (SIS). Stable and radioactive Sn and La beams with an incident energy of 600 MeV per nucleon have been used in order to explore a wide range of isotopic compositions. For the interpretation of the data, calculations with the statistical multifragmentation model for a properly chosen ensemble of excited sources were performed. The parameters of the ensemble, representing the variety of excited spectator nuclei expected in a participant-spectator scenario, are determined empirically by searching for an optimum reproduction of the measured fragment-charge distributions and correlations. An overall very good agreement is obtained. The possible modification of the liquid-drop parameters of the fragment description in the hot freeze-out environment is studied, and a significant reduction of the symmetry-term coefficient is found necessary to reproduce the mean neutron-to-proton ratios <N>/Z and the isoscaling parameters of Z<=10 fragments. The calculations are, furthermore, used to address open questions regarding the modification of the surface-term coefficient at freeze-out, the N/Z dependence of the nuclear caloric curve, and the isotopic evolution of the spectator system between its formation during the initial cascade stage of the reaction and its subsequent breakup.

23 pages, 29 figures, published in Physical Review C

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• Dense Nuclear Matter Equation of State from Heavy-Ion Collisions
• Monte-Carlo generator of heavy ion collisions DCM-SMM
• Formation of hypermatter and hypernuclei within transport models in relativistic ion collisions
• A comparative study of statistical models for nuclear equation of state of stellar matter
• Liquid-Gas phase transition in nuclei
• Formation of hypernuclei in heavy-ion collisions around the threshold energies
• Production of hypernuclei in peripheral relativistic ion collisions
• Tabulated equation of state for supernova matter including full nuclear ensemble
• Dynamical properties and secondary decay effects of projectile fragmentation in 107,124Sn + 120Sn collisions at 600 MeV/nucleon
• Improvements to model of projectile fragmentation
• Experimental reconstruction of primary hot isotopes and characteristic properties of the fragmenting source in the heavy ion reactions near the Fermi energy
• Coupling dynamical and statistical mechanisms for baryonic cluster production in nucleus collisions of intermediate and high energies
• Formation of hypernuclei in evaporation and fission processes
• Symmetry energy from nuclear multifragmentation
• Estimates for temperature in projectile like fragment in geometric and transport models
• Heavy-ion Collisions: Direct and indirect probes of the density and temperature dependence of Esym
• Evaluation of the hyperon binding energy via statistical production of hypernuclei
• Evolution of the statistical disintegration of finite nuclei toward high energy
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• Exploiting neutron-rich radioactive ion beams to constrain the symmetry energy
• Production of light hypernuclei with light-ion beams and targets
• Nucleosynthesis of light nuclei and hypernuclei in central Au+Au collisions at $\sqrt{s_{NN}}$=3 GeV
• The ASY-EOS experiment at GSI: investigating the symmetry energy at supra-saturation densities
• Neutron recognition in the LAND detector for large neutron multiplicity
• Isospin compositions of correlated sources in the Fermi energy domain
• Temperature of projectile like fragments in heavy ion collisions
• The percolation phase transition and statistical multifragmentation in finite systems
• Theoretical Study of Isotope Production in The Peripheral Heavy-ion Collision 136Xe + Pb at 1 GeV/nucleon
• A model for projectile fragmentation
• The effects of medium on nuclear properties in multifragmentation
• Effect of liquid drop model parameters on nuclear liquid gas phase transition
• Statistical approach of nuclear multifragmentation with realistic nuclear equation of state
• On survey of nuclei and hypernuclei in multifragmentation
• Nucleation of baryons in relativistic hadron-nucleus collisions