| Autor: |
Rocchini, M., Garrett, P. E., Zielinska, M., Lenzi, S. M., Dao, D. D., Nowacki, F., Bildstein, V., MacLean, A. D., Olaizola, B., Ahmed, Z. T., Andreoiu, C., Babu, A., Ball, G. C., Bhattacharjee, S. S., Bidaman, H., Cheng, C., Coleman, R., Dillmann, I., Garnsworthy, A. B., Gillespie, S., Griffin, C. J., Grinyer, G. F., Hackman, G., Hanley, M., Illana, A., Jones, S., Laffoley, A. T., Leach, K. G., Lubna, R. S., McAfee, J., Natzke, C., Pannu, S., Paxman, C., Porzio, C., Radich, A. J., Rajabali, M. M., Sarazin, F., Schwarz, K., Shadrick, S., Sharma, S., Suh, J., Svensson, C. E., Yates, D., Zidar, T. |
| Rok vydání: |
2023 |
| Předmět: |
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| Druh dokumentu: |
Working Paper |
| DOI: |
10.1103/PhysRevLett.130.122502 |
| Popis: |
The excited states of $N=44$ $^{74}$Zn were investigated via $\gamma$-ray spectroscopy following $^{74}$Cu $\beta$ decay. By exploiting $\gamma$-$\gamma$ angular correlation analysis, the $2_2^+$, $3_1^+$, $0_2^+$ and $2_3^+$ states in $^{74}$Zn were firmly established. The $\gamma$-ray branching and $E2/M1$ mixing ratios for transitions de-exciting the $2_2^+$, $3_1^+$ and $2_3^+$ states were measured, allowing for the extraction of relative $B(E2)$ values. In particular, the $2_3^+ \to 0_2^+$ and $2_3^+ \to 4_1^+$ transitions were observed for the first time. The results show excellent agreement with new microscopic large-scale shell-model calculations, and are discussed in terms of underlying shapes, as well as the role of neutron excitations across the $N=40$ gap. Enhanced axial shape asymmetry (triaxiality) is suggested to characterize $^{74}$Zn in its ground state. Furthermore, an excited $K=0$ band with a significantly larger softness in its shape is identified. A shore of the $N=40$ ``island of inversion'' appears to manifest above $Z=26$, previously thought as its northern limit in the chart of the nuclides. |
| Databáze: |
arXiv |
| Externí odkaz: |
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