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Evolution of Nuclear Shell Structure due to the Pion Exchange Potential

Wen Hui Long·Hiroyuki Sagawa·Jie Meng·Nguyen Van Giai
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Abstract

The evolution of nuclear shell structure is investigated for the first time within density-dependent relativistic Hartree-Fock theory and the role of $π$-exchange potential is studied in detail. The energy differences between the neutron orbits $\Lrb{\nu1h_{9/2},ν1i_{13/2}}$ in the N=82 isotones and between the proton ones $\Lrb{\pi1g_{7/2},\pi1h_{11/2}}$ in the Z=50 isotopes are extracted as a function of neutron excess $N-Z$. A kink around $Z = 58$ for the N=82 isotones is found as an effect resulting from pion correlations. It is shown that the inclusion of $π$-coupling plays a central role to provide realistic isospin dependence of the energy differences. In particular, the tensor part of the $π$-coupling has an important effect on the characteristic isospin dependence observed in recent experiments.

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Wen Hui Long, Hiroyuki Sagawa, Jie Meng, Nguyen Van Giai. 2006-09-28. Evolution of Nuclear Shell Structure due to the Pion Exchange Potential. https://doi.org/10.1209/0295-5075%2F82%2F12001

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