Generalized time-dependent generator coordinate method for induced fission dynamics

Abstract

The generalized time-dependent generator coordinate method (TD-GCM) is extended to include pairing correlations. The correlated GCM nuclear wave function is expressed in terms of time-dependent generator states and weight functions. The particle−hole channel of the effective interaction is determined by a Hamiltonian derived from an energy density functional, while pairing is treated dynamically in the standard BCS approximation with time-dependent pairing tensor and single-particle occupation probabilities. With the inclusion of pairing correlations, various time-dependent phenomena in open-shell nuclei can be described more realistically. The model is applied to the description of saddle-to-scission dynamics of induced fission. The generalized TD-GCM charge yields and total kinetic energy distribution for the fission of ²⁴⁰Pu, are compared to those obtained using the standard time-dependent density functional theory (TD-DFT) approach, and with available data.

Graphical abstract

Keywords

nuclear density functional theory / generator coordinate method / fission dynamics

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Declarations

The authors declare that they have no competing interests and there are no conflicts.

Acknowledgements

This work was supported in part by the High-end Foreign Experts Plan of China, the National Key R&D Program of China (Contract No. 2018YFA0404400), the National Natural Science Foundation of China (Grant Nos. 12070131001, 11875075, 11935003, 11975031, and 12141501), the High-performance Computing Platform of Peking University, the QuantiXLie Centre of Excellence, a project co-financed by the Croatian Government and European Union through the European Regional Development Fund − the Competitiveness and Cohesion Operational Programme (KK.01.1.1.01.0004), and the Croatian Science Foundation under the project Uncertainty quantification within the nuclear energy density framework (IP-2018-01-5987).

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