Structure of low-lying states in Sm-140 studied by Coulomb excitation

Klintefjord, M.; Hady´nska-Klek, K.; Görgen, A.; Bauer, C.; Garrote, F. L. Bello; Bönig, S.; Bounthong, B.; Damyanova, A.; Delaroche, J.-P.; Fedosseev, V.; Fink, D. A.; Giacoppo, F.; Girod, M.; Hoff, P.; Imai, N.; Korten, W.; Larsen, A.-C.; Libert, J.; Lutter, R.; Marsh, B. A.; Molkanov, P. L.; Naidja, H.; Napiorkowski, P.; Nowacki, F.; Pakarinen, J.; Rapisarda, E.; Reiter, P.; Renstrom, T.; Rothe, S.; Seliverstov, M. D.; Siebeck, B.; Siem, S.; Srebrny, J.; Stora, T.; Thöle, P.; Tornyi, T. G.; Tveten, G. M.; Duppen, P. van; Vermeulen, M. J.; Voulot, D.; Warr, N.; Wenander, F.; Witte, H. de und Zielinska, M. (2016): Structure of low-lying states in Sm-140 studied by Coulomb excitation. In: Physical Review C, Bd. 93, Nr. 5, 54303

Abstract

The electromagnetic structure of Sm-140 was studied in a low-energy Coulomb excitation experiment with a radioactive ion beam from the REX-ISOLDE facility at CERN. The 2(+) and 4(+) states of the ground-state band and a second 2(+) state were populated by multistep excitation. The analysis of the differential Coulomb excitation cross sections yielded reduced transition probabilities between all observed states and the spectroscopic quadrupole moment for the 2(1)(+) state. The experimental results are compared to large-scale shell model calculations and beyond-mean-field calculations based on the Gogny D1S interaction with a five-dimensional collective Hamiltonian formalism. Simpler geometric and algebraic models are also employed to interpret the experimental data. The results indicate that Sm-140 shows considerable. softness, but in contrast to earlier speculation no signs of shape coexistence at low excitation energy. This work sheds more light on the onset of deformation and collectivity in this mass region.

• Dokumententyp: Zeitschriftenartikel
• Fakultät: Physik
• Themengebiete: 500 Naturwissenschaften und Mathematik > 530 Physik
• ISSN: 2469-9985
• Sprache: Englisch