Evidence for a Smooth Onset of Deformation in the Neutron-Rich Kr Isotopes

Phys. Rev. Lett.

108
062701
(2012)
M. Albers, N. Warr, K. Nomura, A. Blazhev, J. Jolie, D. Mücher, B. Bastin, C. Bauer, C. Bernards, L. Bettermann, V. Bildstein, J. Butterworth, M. Cappellazzo, J. Cederkäll, D. Cline, I. Darby, S. Das Gupta, J.M. Daugas, T. Davinson, H. De Witte, J. Diriken, D. Filipescu, E. Fiori, C. Fransen, L.P. Gaffney, G. Georgiev, R. Gernhäuser, M. Hackstein, S. Heinze, H. Hess, M. Huyse, D. Jenkins, J. Konki, M. Kowalczyk, T. Kröll, R. Krücken, J. Litzinger, R. Lutter, N. Marginean, C. Mihai, K. Moschner, P. Napiorkowski, B.S. Nara Singh, K. Nowak, T. Otsuka, J. Pakarinen, M. Pfeiffer, D. Radeck, P. Reiter, S. Rigby, L.M. Robledo, R. Rodriguez-Guzman, M. Rudigier, P. Sarriguren, M. Scheck, M. Seidlitz, B. Siebeck, G. Simpson, P. Thöle, T. Thomas, J. Van de Walle, P. Van Duppen, M. Vermeulen, D. Voulot, R. Wadsworth, F. Wenander, K. Wimmer, K.O. Zell, M. Zielińska

The neutron-rich nuclei  
94,96
 Kr 
  were studied via projectile Coulomb excitation at the REX-ISOLDE facility at CERN. Level energies of the first excited 2+ states and their absolute 𝐸⁢2 transition strengths to the ground state are determined and discussed in the context of the 𝐸⁡(2+
1) and 𝐵⁡(𝐸⁢2;2+
1 →0+
1) systematics of the krypton chain. Contrary to previously published results no sudden onset of deformation is observed. This experimental result is supported by a new proton-neutron interacting boson model calculation based on the constrained Hartree-Fock-Bogoliubov approach using the microscopic Gogny-D1M energy density functional.

DOI
10.1103/PhysRevLett.108.062701
Published on
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