Unambiguous identification of three beta-decaying isomers in 70Cu.
Using resonant laser ionization, beta-decay studies, and for the first time mass measurements, three beta-decaying states have been unambiguously identified in 70Cu. A mass excess of -62 976.1(1.6) keV and a half-life of 44.5(2) s for the (6-) ground state have been determined. The level energies of the (3-) isomer at 101.1(3) keV with T(1/2)=33(2) s and the 1+ isomer at 242.4(3) keV with T(1/2)=6.6(2) s are confirmed by high-precision mass measurements. The low-lying levels of 70Cu populated in the decay of 70Ni and in transfer reactions compare well with large-scale shell-model calculations, and the wave functions appear to be dominated by one proton-one neutron configurations outside the closed Z=28 shell and N=40 subshell. This does not apply to the 1+ state at 1980 keV which exhibits a particular feeding and deexcitation pattern not reproduced by the shell-model calculations.
Van Roosbroeck
J
J
IKS, University of Leuven, Celestijnenlaan 200D, 3001 Leuven, Belgium.
Guénaut
C
C
Audi
G
G
Beck
D
D
Blaum
K
K
Bollen
G
G
Cederkall
J
J
Delahaye
P
P
De Maesschalck
A
A
De Witte
H
H
Fedorov
D
D
Fedoseyev
V N
VN
Franchoo
S
S
Fynbo
H O U
HO
Górska
M
M
Herfurth
F
F
Heyde
K
K
Huyse
M
M
Kellerbauer
A
A
Kluge
H-J
HJ
Köster
U
U
Kruglov
K
K
Lunney
D
D
Mishin
V I
VI
Mueller
W F
WF
Nagy
Sz
S
Schwarz
S
S
Schweikhard
L
L
Smirnova
N A
NA
Van de Vel
K
K
Van Duppen
P
P
Van Dyck
A
A
Walters
W B
WB
Weissman
L
L
Yazidjian
C
C