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Is there np pairing in odd-odd N=Z nuclei?

A. O. Macchiavelli·P. Fallon·R. M. Clark·M. Cromaz·M. A. Deleplanque·R. M. Diamond·G. J. Lane·I. Y. Lee·F. S. Stephens·C. E. Svensson·K. Vetter·D. Ward
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Abstract

The binding energies of even-even and odd-odd N=Z nuclei are compared. After correcting for the symmetry energy we find that the lowest T=1 state in odd-odd N=Z nuclei is as bound as the ground state in the neighboring even-even nucleus, thus providing evidence for isovector np pairing. However, T=0 states in odd-odd N=Z nuclei are several MeV less bound than the even-even ground states. We associate this difference with a pair gap and conclude that there is no evidence for an isoscalar pairing condensate in N=Z nuclei.

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A. O. Macchiavelli, P. Fallon, R. M. Clark, M. Cromaz, M. A. Deleplanque, R. M. Diamond, G. J. Lane, I. Y. Lee, F. S. Stephens, C. E. Svensson, K. Vetter, D. Ward. 1999-07-30. Is there np pairing in odd-odd N=Z nuclei?. https://doi.org/10.1103/physrevc.61.041303

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