Lifetimes of excited states in triaxially deformed 107Tc and 109,111,113Rh

• Published in: The European physical journal. A, Hadrons and nuclei Hadrons and nuclei, 2018-03, Vol.54 (3), p.1-11, Article 50
• Main Authors: Hagen, T. W., Görgen, A., Korten, W., Grente, L., Salsac, M. -D., Farget, F., Braunroth, T., Bruyneel, B., Celikovic, I., Clément, E., de France, G., Delaune, O., Dewald, A., Dijon, A., Hackstein, M., Jacquot, B., Litzinger, J., Ljungvall, J., Louchart, C., Michelagnoli, C., Napoli, D. R., Recchia, F., Rother, W., Sahin, E., Siem, S., Sulignano, B., Theisen, Ch, Valiente-Dobon, J. J.
• Format: Article
• Language: English
• Subjects: Atomic properties; Axial stress; Deformation; Doppler effect; Hadrons; Heavy Ions; Inverse kinematics; Kinematics; Nuclear Fusion; Nuclear Physics; Nuclei (nuclear physics); Parity; Particle and Nuclear Physics; Physics; Physics and Astronomy; Recoil; Regular Article - Experimental Physics; Target recognition
• ISSN: 1434-6001; 1434-601X
• DOI: 10.1140/epja/i2018-12482-9

. Lifetimes of excited states in 107 Tc, 109 Rh, 111 Rh, and 113 Rh were measured at GANIL using the Recoil-Distance Doppler Shift method. The neutron-rich nuclei were produced in fission reactions in inverse kinematics with a 238 U beam impinging on a 9 Be target. Fission fragments were identified event-by-event in the ray-tracing spectrometer VAMOS++ and correlated with prompt γ rays observed around the target position with the EXOGAM Ge detector array. Several lifetimes were obtained for states in the positive-parity yrast bands in the four nuclei and compared to triaxial particle-rotor calculations. The results clarify the configuration for the strongest positive-parity band in 107 Tc and suggest a gradual increase of triaxial deformation with atomic number Z , reaching almost maximum triaxiality for the neutron-rich Rh nuclei.