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arXiv · 1906.10539

Ab initio Gamow in-medium similarity renormalization group with resonance and continuum

B. S. Hu·Q. Wu·Z. H. Sun·F. R. Xu
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Abstract

We have developed a novel ab initio Gamow in-medium similarity renormalization group (Gamow IMSRG) in the complex-energy Berggren framework. The advanced Gamow IMSRG is capable of describing the resonance and nonresonant continuum properties of weakly bound and unbound nuclear many-body systems. As test grounds, carbon and oxygen isotopes have been calculated with chiral two- and three-nucleon forces from the effective field theory. Resonant states observed in the neutron-dripline 24O are well reproduced. The halo structure of the known heaviest Borromean nucleus 22C is clearly seen by calculating the density distribution in which the continuum s channel plays a crucial role. Furthermore, we predict low-lying resonant excited states in 22C. The Gamow IMSRG provides tractable ab initio calculations of weakly bound and unbound open quantum systems.

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B. S. Hu, Q. Wu, Z. H. Sun, F. R. Xu. 2019-06-23. Ab initio Gamow in-medium similarity renormalization group with resonance and continuum. https://doi.org/10.1103/physrevc.99.061302

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