Shape coexistence at the proton drip-line: First identification of excited states in 180Pb

P. Rahkila , D. G. Jenkins , J. Pakarinen , C. Gray-Jones , P. T. Greenlees , U. Jakobsson , P. Jones , R. Julin , S. Juutinen , S. Ketelhut , H. Koivisto , M. Leino , P. Nieminen , M. Nyman , P. Papadakis , S. Paschalis , M. Petri , P. Peura , O. J. Roberts , T. Ropponen , P. Ruotsalainen , J. Saren , C. Scholey , J. Sorri , A. G. Tuff , J. Uusitalo , R. Wadsworth , M. Bender (1) , P.-H. Heenen

1 CENBG - Centre d'Etudes Nucléaires de Bordeaux Gradignan

Excited states in the extremely neutron-deficient nucleus 180Pb have been identified for the first time using the JUROGAM II array in conjunction with the RITU recoil separator at the Accelerator Laboratory of the University of Jyv¨askyl¨a. This study lies at the limit of what is presently achievable with in-beam spectroscopy, with an estimated cross section of only 10 nb for the 92Mo(90Zr,2n)180Pb reaction. A continuation of the trend observed in 182Pb and 184Pb is seen, where the prolate minimum continues to rise beyond the N = 104 midshell with respect to the spherical ground state. Beyond-mean-field calculations are in reasonable correspondence with the trends deduced from experiment.

Domaines: Physique Nucléaire Théorique [nucl-th]

P. Rahkila, D. G. Jenkins, J. Pakarinen, C. Gray-Jones, P. T. Greenlees, et al.. Shape coexistence at the proton drip-line: First identification of excited states in 180Pb. Physical Review C, 2010, 82, pp.011303. ⟨10.1103/PhysRevC.82.011303⟩. ⟨in2p3-00529450⟩