| Autor: |
Ajayi, Samuel, Tripathi, Vandana, Rubino, E., Bhattacharya, Soumik, Baby, L. T., Lubna, R. S., Benetti, C., Wibisono, Catur, Wheeler, MacMillan B., Tabor, S. L., Utsuno, Yutaka, Shimizu, Noritaka, Allmond, J. M. |
| Rok vydání: |
2023 |
| Předmět: |
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| Druh dokumentu: |
Working Paper |
| Popis: |
High spin states in $^{59}$Co ($Z=27$), $^{59}$Ni ($Z=28$) and $^{61}$Co have been populated by the fusion evaporation reactions, $^{48}$Ti($^{14}$C, p2n)$^{59}$Co, $^{48}$Ti($^{14}$C, 3n)$^{59}$Ni, and $^{50}$Ti($^{14}$C, p2n)$^{61}$Co. The 9 MV tandem accelerator at the John D Fox Laboratory, Florida State University (FSU) was used to accelerate the $^{14}$C beam and the de-exciting $\gamma$ rays were detected by the FSU detector array consisting of six High Purity Germanium (HPGe) clover detectors, and three single crystals. Directional correlation of the $\gamma$ rays de-exciting oriented states (DCO ratios) and polarization asymmetry measurements helped to establish spin and parities of the excited states whenever possible. The level scheme of $^{59}$Co has been expanded with the inclusion of positive parity states up to 31/2$^+$ at around 11 MeV. The $^{59}$Ni positive parity states known from previous study were verified with modifications to some of the spins and parities. On the other hand, the negative parity states were extended to 31/2 at an excitation energy of 12 MeV. No new transition was observed for $^{61}$Co, but one of the major bands has been reassigned as consisting of positive parity states by reason of this study which is a candidate for magnetic rotation band. Cross shell excitations were observed in the three nuclei studied and the prominent role of excitation to g$_{9/2}$ orbital crossing the $N=40$ shell gap was established in relation to collective excitation in these nuclei by comparison with large-scale shell model calculations. |
| Databáze: |
arXiv |
| Externí odkaz: |
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