Isoscaling in Statistical Sequential Decay Model.

A sequential decay model is used to study isoscaling, i.e. the factorization of the isotope ratios from sources of different isospins and sizes over a broad range of excitation energies, into fugacity terms of proton and neutron number, R21(N,Z) = Y2(N,Z)/Y1(N,Z) = Ce(?N+?Z). It is found that the isoscaling parameters ?and ?have a strong dependence on the isospin difference of equilibrated source and excitation energy, no significant influence of the source size on ?and ?has been observed. It is found that ?and ?decrease with the excitation energy and are linear functions of 1/Tand ?(Z/A)2or ?(N/A)2of the sources. Symmetry energy coefficient Csymis constrained from the relationship of ?and source ?(Z/A)2, ?and source ?(N/A)2. [ABSTRACT FROM AUTHOR]