Shape coexistence revealed in the N=Z isotope 72Kr through inelastic scattering

• Published in: The European physical journal. A, Hadrons and nuclei Vol. 56; no. 6
• Main Authors: Wimmer, K., Arici, T., Korten, W., Doornenbal, P., Delaroche, J.-P., Girod, M., Libert, J., Rodríguez, T. R., Aguilera, P., Algora, A., Ando, T., Baba, H., Blank, B., Boso, A., Chen, S., Corsi, A., Davies, P., de Angelis, G., de France, G., Doherty, D. T., Gerl, J., Gernhäuser, R., Goigoux, T., Jenkins, D., Kiss, G., Koyama, S., Motobayashi, T., Nagamine, S., Niikura, M., Nishimura, S., Obertelli, A., Lubos, D., Phong, V. H., Rubio, B., Sahin, E., Saito, T. Y., Sakurai, H., Sinclair, L., Steppenbeck, D., Taniuchi, R., Vaquero, V., Wadsworth, R., Wu, J., Zielinska, M.
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 2020; Springer Nature B.V
• Subjects: Hadrons; Heavy Ions; Inelastic scattering; Nuclear deformation; Nuclear Fusion; Nuclear Physics; Particle and Nuclear Physics; Physics; Physics and Astronomy; Regular Article - Experimental Physics; Transition probabilities
• ISSN: 1434-6001; 1434-601X
• DOI: 10.1140/epja/s10050-020-00171-3

The N = Z = 36 nucleus 72 Kr has been studied by inelastic scattering at intermediate energies. Two targets, 9 Be and 197 Au, were used to extract the nuclear deformation length, δ N , and the reduced E 2 transition probability, B ( E 2). The previously unknown non-yrast 2 + and 4 + states as well as a new candidate for the octupole 3 - state have been observed in the scattering on the Be target and placed in the level scheme based on γ - γ coincidences. The second 2 + state was also observed in the scattering on the Au target and the B ( E 2 ; 2 2 + → 0 1 + ) value could be determined for the first time. Analyzing the results in terms of a two-band mixing model shows clear evidence for a oblate-prolate shape coexistence and can be explained by a shape change from an oblate ground state to prolate deformed yrast band from the first 2 + state. This interpretation is corroborated by beyond mean field calculations using the Gogny D1S interaction.