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Competition between isoscalar and isovector pairing correlations in N=Z nuclei

Kazunari Kaneko·Munetake Hasegawa
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Abstract

We study the isoscalar (T=0) and isovector (T=1) pairing correlations in N=Z nuclei. They are estimated from the double difference of binding energies for odd-odd N=Z nuclei and the odd-even mass difference for the neighboring odd-mass nuclei, respectively. The empirical and BCS calculations based on a T=0 and T=1 pairing model reproduce well the almost degeneracy of the lowest T=0 and T=1 states over a wide range of even-even and odd-odd N=Z nuclei. It is shown that this degeneracy is attributed to competition between the isoscalar and isovector pairing correlations in N=Z nuclei. The calculations give an interesting prediction that the odd-odd N=Z nucleus 82Nb has possibly the ground state with T=0.

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Kazunari Kaneko, Munetake Hasegawa. 2004-04-02. Competition between isoscalar and isovector pairing correlations in N=Z nuclei. https://doi.org/10.1103/physrevc.69.061302

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