g Factor of the Zr-99 (7/2(+)) Isomer: Monopole Evolution in the Shape-Coexisting Region

Boulay, F; Simpson, GS; Ichikawa, Y; Kisyov, S; Bucurescu, D; Takamine, A; Ahn, DS; Asahi, K; Baba, H; Balabanski, DL; Egami, T; Fujita, T; Fukuda, N; Funayama, C; Furukawa, T; Georgiev, G; Gladkov, A; Hass, M; K., Imamura; Inabe, N; Ishibashi, Y; Kawaguchi, T; Kawamura, T; Kim, W; Kobayashi, Y; Kojima, S; Kusoglu, A; Lozeva, R; Momiyama, S; Mukul, I; Niikura, M; Nishibata, H; Nishizaka, T; Odahara, A; Ohtomo, Y; Ralet, D; Sato, T; Shimizu, Y; Sumikama, T; Suzuki, H; Takeda, H; Tao, LC; Togano, Y; Tominaga, D; Ueno, H; Yamazaki, H; Yang, XF; Daugas, JM; Parnefjord Gustafsson, Fredrik

doi:10.1103/PhysRevLett.124.112501

g Factor of the Zr-99 (7/2(+)) Isomer: Monopole Evolution in the Shape-Coexisting Region

Author:

Boulay, F

Simpson, GS ; Ichikawa, Y ; Kisyov, S ; Bucurescu, D ; Takamine, A ; Ahn, DS ; Asahi, K ; Baba, H ; Balabanski, DL ; Egami, T ; Fujita, T ; Fukuda, N ; Funayama, C ; Furukawa, T ; Georgiev, G ; Gladkov, A ; Hass, M ; K., Imamura ; Inabe, N ; Ishibashi, Y ; Kawaguchi, T ; Kawamura, T ; Kim, W ; Kobayashi, Y ; Kojima, S ; Kusoglu, A ; Lozeva, R ; Momiyama, S ; Mukul, I ; Niikura, M ; Nishibata, H ; Nishizaka, T ; Odahara, A ; Ohtomo, Y ; Ralet, D ; Sato, T ; Shimizu, Y ; Sumikama, T ; Suzuki, H ; Takeda, H ; Tao, LC ; Togano, Y ; Tominaga, D ; Ueno, H ; Yamazaki, H ; Yang, XF ; Daugas, JM ; Parnefjord Gustafsson, Fredrik

Keywords:

Science & Technology, Physical Sciences, Physics, Multidisciplinary, Physics, BOSON-FERMION MODEL, RIKEN, LEVEL, IDENTIFICATION, SEPARATION, BIGRIPS, STATES, 01 Mathematical Sciences, 02 Physical Sciences, 09 Engineering, General Physics, 40 Engineering, 49 Mathematical sciences, 51 Physical sciences

Abstract:

The gyromagnetic factor of the low-lying E=251.96(9) keV isomeric state of the nucleus ^{99}Zr was measured using the time-dependent perturbed angular distribution technique. This level is assigned a spin and parity of J^{π}=7/2^{+}, with a half-life of T_{1/2}=336(5) ns. The isomer was produced and spin aligned via the abrasion-fission of a ^{238}U primary beam at RIKEN RIBF. A magnetic moment |μ|=2.31(14)μ_{N} was deduced showing that this isomer is not single particle in nature. A comparison of the experimental values with interacting boson-fermion model IBFM-1 results shows that this state is strongly mixed with a main νd_{5/2} composition. Furthermore, it was found that monopole single-particle evolution changes significantly with the appearance of collective modes, likely due to type-II shell evolution.