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

Journal Article · Tue Aug 15 04:00:00 EDT 2006 · Physical Review. C, Nuclear Physics

DOI:https://doi.org/10.1103/PHYSREVC.74.024605· OSTI ID:20863728

Iglio, J; Shetty, D V; Yennello, S J; Souliotis, G A; Jandel, M; Keksis, A L; Soisson, S N; Stein, B C; Wuenschel, S; Botvina, A S ^[1]

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1. Cyclotron Institute, Texas A and M University, College Station, Texas 77843 (United States)

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.

• OSTI ID: 20863728
• Journal Information: Physical Review. C, Nuclear Physics, Journal Name: Physical Review. C, Nuclear Physics Journal Issue: 2 Vol. 74; ISSN 0556-2813; ISSN PRVCAN
• Country of Publication: United States
• Language: English

Related Subjects

73 NUCLEAR PHYSICS AND RADIATION PHYSICS
ARGON 40 REACTIONS
ASYMMETRY
CALCIUM 40 REACTIONS
ENERGY DENSITY
EXCITATION
GROUND STATES
HOT NUCLEI
IRON 58 TARGET
ISOSPIN
MEV RANGE
NEUTRONS
NICKEL 58 TARGET
NUCLEAR DECAY
NUCLEAR FRAGMENTATION
NUCLEAR FRAGMENTS
NUCLEAR REACTION YIELD
PROTONS
SYMMETRY