Signatures of triaxiality in low-spin spectra of $^{86}$Ge

M. Lettmann , V. Werner , N. Pietralla , P. Doornenbal , A. Obertelli (1) , T.R. Rodríguez , K. Sieja (2) , G. Authelet (1) , H. Baba , D. Calvet (1) , F. Château (1) , S. Chen , A. Corsi (1) , A. Delbart (1) , J.M. Gheller (1) , A. Giganon (1) , A. Gillibert (1) , V. Lapoux (1) , T. Motobayashi , M. Niikura , N. Paul (1) , J.Y. Roussé (1) , H. Sakurai , C. Santamaria (1) , D. Steppenbeck , R. Taniuchi , T. Uesaka , T. Ando , T. Arici , A. Blazhev , F. Browne , A. Bruce , R.J. Caroll , L.X. Chung , M.L. Cortés , M. Dewald , B. Ding , F. Flavigny (3) , S. Franchoo (3) , M. Górska , A. Gottardo (3) , A. Jungclaus , J. Lee , B.D. Linh , J. Liu , Z. Liu , C. Lizarazo , S. Momiyama , K. Moschner , S. Nagamine , N. Nakatsuka , C. Nita , C.R. Nobs , L. Olivier (3) , Z. Patel , Zs. Podolyák , M. Rudigier , T. Saito , C. Shand , P.A. Söderström , I. Stefan (3) , V. Vaquero , K. Wimmer , Z. Xu

1 DPHN - Département de Physique Nucléaire (ex SPhN)
2 IPHC - Institut Pluridisciplinaire Hubert Curien
3 IPNO - Institut de Physique Nucléaire d'Orsay

Low-spin states of neutron-rich 84,86,88Ge were measured by in-flight γ-ray spectroscopy at 270 MeV/u at the RIKEN-RIBF facility. The exotic beams have been produced by primary 238U in-flight fission reactions and impinged on the MINOS device. MINOS combines a 10-cm long LH2 target with a Time Projection Chamber (TPC) to reconstruct the reaction vertices. The reactions were selected by the BigRIPS and the ZeroDegree spectrometers for the incoming and outgoing channels, respectively. Emitted γ radiation was detected by the NaI-array DALI2. De-excitations from the , , and states of 84,86Ge and and states of 88Ge were observed. The data are compared to state-of-the-art shell model and beyond-mean-field calculations. Furthermore, a candidate for a state of 86Ge was identified. This state plays a key role in the discussion of ground-state triaxiality of 86Ge, along with other features of the low-energy level scheme. This work was published in [1].

Domaines: Physique Nucléaire Expérimentale [nucl-ex]

M. Lettmann, V. Werner, N. Pietralla, P. Doornenbal, A. Obertelli, et al.. Signatures of triaxiality in low-spin spectra of $^{86}$Ge. 22nd International School on Nuclear Physics, Neutron Physics and Applications, Sep 2017, Varna, Bulgaria. pp.012023, ⟨10.1088/1742-6596/1023/1/012023⟩. ⟨hal-01815269⟩