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arXiv · 0705.2587

Isospin mixing in a particle-number conserving microscopic approach

L. Bonneau·J. Bartel·P. Quentin
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Abstract

We calculate the isospin-mixing parameter for several Tz=-1, Tz=0 and Tz=1 nuclei from Mg to Sn in the particle-number conserving Higher Tamm-Dancoff approach taking into account the pairing correlations. In particular we investigate the role of the Coulomb interaction and the |Tz|=1 pairing correlations. To do so the HTDA approach is implemented with the SIII Skyrme effective nucleon-nucleon interaction in the mean-field channel and a delta interaction in the pairing channel. We conclude from this investigation that the pairing correlations bring a large contribution to isospin-symmetry breaking, whereas the Coulomb interaction turns out to play a less important role. Moreover we find that the isospin-mixing parameters for Tz=-1 and Tz=1 nuclei are comparable while they are about twice as large for Tz=0 nuclei (between 3% and 6%, including doubly magic nuclei).

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L. Bonneau, J. Bartel, P. Quentin. 2007-05-17. Isospin mixing in a particle-number conserving microscopic approach. https://arxiv.org/abs/0705.2587

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