| Autor: |
Miernik, K., Korgul, A., Poklepa, W., Wilson, J. N., Charles, G., Czajkowski, S., Czyż, P., Fijałkowska, A., Fraile, L. M., Garczyński, P., Hauschild, K., Hiver, C., Kurtukian-Nieto, T., Lebois, M., Llanos, M., Lopez-Martens, A., Treasa, K. M. Deby, Ljungvall, J., Matea, I., Mielczarek, J., Murias, J. R., Pasqualato, G., Skruch, A., Solak, K., Stoyachev, K., Tsekhanovich, I. |
| Rok vydání: |
2023 |
| Předmět: |
|
| Druh dokumentu: |
Working Paper |
| DOI: |
10.1103/PhysRevC.108.054608 |
| Popis: |
Background: Asymmetric fission is known to occur in two regions, the actinides and sub-lead, and is dependent on the fissioning system excitation energy. Experimental evidence in the sub-lead region show that this mode is surprisingly persistent with increasing energy and its origin is not fully understood. Purpose: To experimentally study the fusion-fission reaction of $^{215}$Fr at moderate excitation energy and determine previously unknown independent fission yields and other properties. Method: The compound nucleus was formed in the reaction $^{18}$O + $^{197}$Au. The prompt gamma-rays emitted during the reaction were measured with the high efficiency and high granularity $\nu$-ball2 spectrometer. Independent fission yields of even-even nuclei were determined by detecting triple-gamma cascades in the fission fragments. Results: The observed yields, although dominated by a symmetric peak, show maxima for heavy fragment of $Z \approx 54-56$, which is consistent with the known results in the actinide region but unexpected for the nuclide of interest, and at the studied excitation energy. Conclusions: The mode of asymmetric fission is present even at relatively high excitation energies in the system studied. This observation matches experimental findings in the sub-lead region, contrary to the actinides, and so far there is no well-developed explanation of this phenomenon. |
| Databáze: |
arXiv |
| Externí odkaz: |
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