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تسجيل مستخدم جديدAnomalous behavior of the first excited 0$^{+}$ state in $N approx Z$ nuclei
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A study of the energies of the first excited $0^+$ states in all even-even $Z$ $geq$ 8 nuclei reveals an anomalous behavior in some nuclei with $N$ = $Z$, $Z$ $pm$ 2. We analyze these irregularities in the framework of the shell model. It is shown that proton-neutron correlations play an important role in this phenomenon.
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