Shape coexistence in light se isotopes: evidence for oblate shapes.
Lifetimes of states in the ground-state bands of (70)Se and (72)Se were measured using the recoil-distance Doppler shift method. The results deviate significantly from earlier measurements, requiring a revision of the conclusions drawn from a recent Coulomb excitation experiment concerning the shape of (70)Se. The new results lead to a coherent picture of shape coexistence in the neutron-deficient selenium and krypton isotopes. The coexistence and evolution of oblate and prolate shapes in this mass region is for the first time consistently described by new Hartree-Fock-Bogolyubov-based configuration-mixing calculations which were performed using the Gogny D1S interaction.
Ljungvall
J
J
CEA-Saclay, DAPNIA/SPhN, F-91191 Gif-sur-Yvette Cedex, France.
Görgen
A
A
Girod
M
M
Delaroche
J-P
JP
Dewald
A
A
Dossat
C
C
Farnea
E
E
Korten
W
W
Melon
B
B
Menegazzo
R
R
Obertelli
A
A
Orlandi
R
R
Petkov
P
P
Pissulla
T
T
Siem
S
S
Singh
R P
RP
Srebrny
J
J
Theisen
C H
CH
Ur
C A
CA
Valiente-Dobón
J J
JJ
Zell
K O
KO
Zielińska
M
M