Three-dimensional Skyrme Hartree-Fock-Bogoliubov solver in coordinate-space representation

The coordinate-space representation of the Hartree-Fock-Bogoliubov theory is the method of choice to study weakly bound nuclei whose properties are affected by the quasiparticle continuum space. To describe such systems, we developed a three-dimensional Skyrme-Hartree-Fock-Bogoliubov solverHFBFFTbased on the existing, highly optimized and parallelized Skyrme-Hartree-Fock codeSky3D. The code does not impose any self-consistent spatial symmetries such as mirror inversions or parity. The underlying equations are solved inHFBFFTdirectly in the canonical basis using the fast Fourier transform. To remedy the problems with pairing collapse, we implemented the soft energy cutoff and pairing annealing. The convergence of HFB solutions was improved by a sub-iteration method. The Hermiticity violation of differential operators brought by Fourier-transform-based differentiation has also been solved. The accuracy and performance ofHFBFFTwere tested by benchmarking it against other HFB codes, both spherical and deformed, for a set of nuclei, both well-bound and weakly-bound. Published by Elsevier B.V.

Automated summary

The HFBFFT solver, based on Sky3D code, is developed to study the weakly bound nuclei affected by the quasiparticle continuum space. It solves the underlying equations directly in the canonical basis using fast Fourier transform, and implements measures like soft energy cutoff and pairing annealing to address the problems encountered in the pairing collapse. The accuracy and performance of HFBFFT have been tested and compared with other HFB codes for various nuclei.