Isospin Fractionation in Nuclear Multifragmentation

Abstract

Isotope, isotone and isobar yield ratios are utilized to obtain an estimate of the isotopic composition of the gas phase, i.e., the relative abundance of free neutrons and protons at breakup. Within the context of equilibrium calculations, these analyses indicate that the gas phase is enriched in neutrons relative to the liquid phase represented by bound nuclei.

Generalized isoscaling of isotopic distributions

“…[ 28,29] and justified therein by statistical model calculations [30], which suggests that secondary decay corrections largely cancel when the two systems are at the same temperature. Likewise, this approach has also been taken with the isotope thermometric expression in Eq.…”

“…Earlier observation of isoscaling law suggests that the sequential decay correction appears to behave as a multiplicative factor to the primary yield in Eq. 3 [28]. In this case, the temperature dependent secondary decay for two different temperature is included in the normalization constant, CÕ, in Eq.…”

“…Here, we focus upon the description of isotopic data where thermal models have suggested an isotopic thermometer obtained from a double ratio of isotopic yields and an isoscaling relationship obtained from a single ratio of isotopic yields. The isoscaling relationship provides a remarkably accurate way to relate data for systems of different isotopic composition but with approximately the same excitation energy per nucleon or temperature [8,[28][29][30].…”

Effect of isospin-dependent cluster recognition on the observables in heavy ion collisions

“…The isoscaling parameter α can be used to estimate the enhancement of neutron rich isotopes, and has been used as a probe to study the density dependence of symmetry energy [21,30,31,34]. We analyze the isoscaling relationship with both cluster recognition methods for fragments with Z = 3 − 8.…”

Systematic study of the symmetry energy within the approach of the statistical multifragmentation model

“…A systematic study on the effect of the secondary decay as predicted by the Statistical Multifragmentation Model (SMM) [7] is presented in this report, with particular emphasis on the comparison between the recently proposed isobaric yield ratio method [8] and the well known isoscaling [6,[9][10][11][12][13]. To ascertain the degree of confidence that can be obtained in experimental results, the correlation between input values and the quantities that can be extracted from secondary fragments was established.…”