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Proton-neutron pairing in the deformed BCS approach

Fedor Simkovic·Charal Moustakidis·Larisa Pacearescu·Amand Faessler
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Abstract

We examine isovector and isoscalar proton-neutron pairing correlations for the ground state of even-even Ge isotopes with mass number A=64-76 within the deformed BCS approach. For N=Z 64Ge the BCS solution with only T=0 proton-neutron pairs is found. For other nuclear systems (N>Z) a coexistence of a T=0 and T=1 pairs in the BCS wave function is observed. A problem of fixing of strengths of isoscalar and isovector pairing interactions is addressed. A dependence of number of like and unlike pairs in the BCS ground state on the difference between number of neutrons and protons is discussed. We found that for nuclei with N much bigger than Z the effect of proton-neutron pairing is small but not negligible.

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Fedor Simkovic, Charal Moustakidis, Larisa Pacearescu, Amand Faessler. 2003-08-15. Proton-neutron pairing in the deformed BCS approach. https://doi.org/10.1103/physrevc.68.054319

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