A systematics for negative pion induced nuclear fission cross-sections: Experimental data fitting and cascade exciton model validation

Abstract

The developed fission systematics depicts the projectile energy and the target mass dependence of fission cross-sections of heavy nuclei. The developed model is fitted using experimental fission cross-section data of 500–1665 MeV negative pion induced fission in [Formula: see text]Sn, [Formula: see text]Au and [Formula: see text]Bi. The same systematics is further fitted using the cascade exciton model (CEM) calculations of the above-mentioned fission reactions. Parameterization of the model is performed by calculating its parameters and uncertainties in them. A comparison of the systematics predictions with experimental data and CEM calculations is made. Validation of the systematics using new target nuclei [Formula: see text]Eu, [Formula: see text]Ta, [Formula: see text]Hg and [Formula: see text]At (not included in the systematics development) over an extended range of pion energies, from 80 MeV to 2500 MeV, builds trust in it. The systematics is not valid for [Formula: see text]Th and [Formula: see text]U. The systematics is found to be valid for target nuclei from [Formula: see text]Sn to [Formula: see text]At and for incident negative pion energies from 80 MeV to 2500 MeV. Results are discussed in detail. Merits and demerits of the developed systematics have been concisely described. Valid conclusions and future perspectives are also given.