Study of Isoscaling with Statistical Multifragmentation Models

Source: arXiv


Different statistical multifragmentation models have been used to study isoscaling, i.e. the factorization of the isotope ratios from two reactions, into fugacity terms of proton and neutron number, R21(N,Z)=Y2(N,Z)/Y1(N,Z)=C*exp(a*N+b*Z). Even though the primary isotope distributions are quite different from the final distributions due to evaporation from the excited fragments, the values of a and b are not much affected by sequential decays. a is shown to be mainly sensitive to the proton and neutron composition of the emitting source and may be used to study isospin-dependent properties in nuclear collisions such as the symmetry energy in the equation of state of asymmetric nuclear matter.

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    • "where α and β are fitting parameters. Equations of the form of (1) can be linked, under some approximations, to primary isotope yields produced by disassembling infinite equilibrated systems in microcanonical and grand canonical ensembles [4], as well as to breakups in canonical [6] ensembles. Little reflection is needed to understand that R 21 could be affected by many reaction variables. "
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    Physical Review C 04/2005; 73(4). DOI:10.1103/PhysRevC.73.044601 · 3.73 Impact Factor
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    ABSTRACT: Calculations for a set of nuclear multifragmentation data are made using a Canonical and a Grand Canonical Model. The physics assumptions are identical but the Canonical Model has an exact number of particles, whereas, the Grand Canonical Model has a varying number of particles, hence, is less exact. Interesting differences are found. Comment: 12 pages, Revtex, and 3 postscript figures
    Physical Review C 06/2001; 64(4). DOI:10.1103/PhysRevC.64.044608 · 3.73 Impact Factor
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    Acta Physica Polonica Series B 07/2001; 33(7). · 0.85 Impact Factor
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