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arXiv · 1608.08312

New concept for pairing anti-halo effect as a localized wave packet of quasi-particle

K. Hagino·H. Sagawa
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Abstract

The pairing anti-halo effect is a phenomenon that a pairing correlation suppresses a divergence of nuclear radius, which happens for single-particle states with orbital angular momenta of $l$ = 0 and 1 in the limit of vanishing binding energy. While this effect has mainly been discussed in terms of Hartree-Fock-Bogoliubov (HFB) theory, we here use a three-body model and provide its new intuitive concept as a localized wave packet for a quasi-particle, that is, a coherent superposition of a weakly bound and continuum wave functions due to a pairing interaction. We show that the one-particle density in the three-body model can be directly expressed with such quasi-particle wave functions, which have a close analog to wave functions in the HFB approximation.

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K. Hagino, H. Sagawa. 2016-08-30. New concept for pairing anti-halo effect as a localized wave packet of quasi-particle. https://doi.org/10.1103/physrevc.95.024304

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