B. C. Stein

Symmetry energy and the isospin dependent equation of state

We show that the large sequential decay corrections obtained by Ono {\it et al} [nucl-ex/0507018], is in contradiction with both the other dynamical and statistical model calculations carried out for the same systems and energy. On the other hand, the conclusion of Shetty {\it {et al.}}

Measuring the temperature of hot nuclear fragments

[

Constraining the symmetry term in the nuclear equation of state at subsaturation densities and finite temperatures

Phys. Rev. C 70, 011601R (2004)

Symmetry energy and the isoscaling properties of the fragments produced in Ar 40 , Ca 40 + Fe 58 , Ni 58 reactions at 25, 33, 45, and 53 MeV/nucleon

]

Isoscaling of fragments with Z = 1 − 17 from reconstructed quasiprojectiles

, that the experimental data favors Gogny

Analysis of fragment yield ratios in the nuclear phase transition

-

Quantum suppression of fluctuations and temperatures of reconstructed A ∼ 30 quasi-projectiles

AS interaction (obtained assuming a significantly smaller sequential decay effects), is consistent with several other independent studies.

Nuclear expansion and symmetry energy of hot nuclei

Abstract A new thermometer based on fragment momentum fluctuations is presented. This thermometer exhibited residual contamination from the collective motion of the fragments along the beam axis. For this reason, the transverse direction has been explored. Additionally, a mass dependence was observed for this thermometer. This mass dependence may be the result of the Fermi momentum of nucleons or the different properties of the fragments (binding energy, spin, etc.) which might be more sensitive to different densities and temperatures of the exploding fragments. We expect some of these aspects to be smaller for protons (and/or neutrons); consequently, the proton transverse momentum fluctuations were used to investigate the temperature dependence of the source.

Recent Updates to the FAUST Array

Methods of extraction of the symmetry energy (or enthalpy) coefficient to temperature ratio from isobaric and isotopic yields of fragments produced in Fermi-energy heavy-ion collisions are discussed. We show that the methods are consistent when the hot fragmenting source is well characterized and its excitation energy and isotopic composition are properly taken into account. The results are independent of the mass number of the detected fragments, which suggests that their fate is decided very early in the reaction.

ROLE OF QUASIPROJECTILE ISOSPIN ASYMMETRY IN NUCLEAR FRAGMENTATION

The symmetry energy and the isoscaling properties of the fragments produced in the multifragmentation of {sup 40}Ar, {sup 40}Ca+{sup 58}Fe, {sup 58}Ni reactions at 25, 33, 45, and 53 MeV/nucleon were investigated within the framework of statistical multifragmentation model. The isoscaling parameters {alpha}, from the primary (hot) and secondary (cold) fragment yield distributions, were studied as a function of excitation energy, isospin (neutron-to-proton asymmetry), and fragment symmetry energy. It is observed that the isoscaling parameter {alpha} decreases with increasing excitation energy and decreasing symmetry energy. The parameter {alpha} is also observed to increase with increasing difference in the isospin of the fragmenting system. The sequential decay of the primary fragments into secondary fragments, when studied as a function of excitation energy and isospin of the fragmenting system, show very little influence on the isoscaling parameter. The symmetry energy, however, has a strong influence on the isospin properties of the hot fragments. The experimentally observed scaling parameters can be explained by symmetry energy that is significantly lower than that for the ground-state nuclei near saturation density. The results indicate that the properties of hot nuclei at excitation energies, densities, and isospin away from the normal ground-state nuclei could be significantly different.