Evidence for Coexisting Shapes through Lifetime Measurements in $^{98}\mathrm{Zr}$

Singh, P; Korten, W; Hagen, TW; Görgen, A; Grente, L; Salsac, M-D; Farget, F; Clément, E; de France, G; Braunroth, T; Bruyneel, B; Celikovic, I; Delaune, O; Dewald, A; Dijon, A; Delaroche, J-P; Girod, M; Hackstein, M; Jacquot, B; Libert, J; Litzinger, J; Ljungvall, J; Louchart, C; Gottardo, A; Michelagnoli, C; Müller-Gatermann, C; Napoli, DR; Otsuka, T; Pillet, N; Recchia, F; Rother, W; Sahin, E; Siem, S; Sulignano, B; Togashi, T; Tsunoda, Y; Theisen, C; Valiente-Dobon, JJ

doi:10.1103/PhysRevLett.121.192501

Evidence for Coexisting Shapes through Lifetime Measurements in $^{98}\mathrm{Zr}$

Author:

Singh, P

Korten, W ; Hagen, TW ; Görgen, A ; Grente, L ; Salsac, M-D ; Farget, F ; Clément, E ; de France, G ; Braunroth, T ; Bruyneel, B ; Celikovic, I ; Delaune, O ; Dewald, A ; Dijon, A ; Delaroche, J-P ; Girod, M ; Hackstein, M ; Jacquot, B ; Libert, J ; Litzinger, J ; Ljungvall, J ; Louchart, C ; Gottardo, A ; Michelagnoli, C ; Müller-Gatermann, C ; Napoli, DR ; Otsuka, T ; Pillet, N ; Recchia, F ; Rother, W ; Sahin, E ; Siem, S ; Sulignano, B ; Togashi, T ; Tsunoda, Y ; Theisen, C ; Valiente-Dobon, JJ

Keywords:

Science & Technology, Physical Sciences, Physics, Multidisciplinary, Physics, NEUTRON-RICH, FISSION FRAGMENTS, CHARGE RADII, STATES, ISOTOPES, ZR, SPECTROMETER, PERFORMANCE, EVOLUTION, NUCLEI, 01 Mathematical Sciences, 02 Physical Sciences, 09 Engineering, General Physics, 40 Engineering, 49 Mathematical sciences, 51 Physical sciences

Abstract:

The lifetimes of the first excited 2^{+}, 4^{+}, and 6^{+} states in ^{98}Zr were measured with the recoil-distance Doppler shift method in an experiment performed at GANIL. Excited states in ^{98}Zr were populated using the fission reaction between a 6.2 MeV/u ^{238}U beam and a ^{9}Be target. The γ rays were detected with the EXOGAM array in correlation with the fission fragments identified by mass and atomic number in the VAMOS++ spectrometer. Our result shows a very small B(E2;2_{1}^{+}→0_{1}^{+}) value in ^{98}Zr, thereby confirming the very sudden onset of collectivity at N=60. The experimental results are compared to large-scale Monte Carlo shell model and beyond-mean-field calculations. The present results indicate the coexistence of two additional deformed shapes in this nucleus along with the spherical ground state.