New features of shape coexistence in ;{152}Sm.
Excited states in ;{152}Sm have been investigated with the ;{152}Sm(n,n;{'}gamma) reaction. The lowest four negative-parity band structures have been characterized in detail with respect to their absolute decay properties. Specifically, a new K;{pi} = 0;{-} band has been assigned with its 1;{-} band head at 1681 keV. This newly observed band has a remarkable similarity in its E1 transition rates for decay to the first excited K;{pi} = 0;{+} band at 684 keV to the lowest K;{pi} = 0;{-} band and its decay to the ground-state band. Based on these decay properties, as well as energy considerations, this new band is assigned as a K;{pi} = 0;{-} octupole excitation based on the K;{pi} = 0_{2};{+} state. An emerging pattern of repeating excitations built on the 0_{2};{+} level similar to those built on the ground state may indicate that ;{152}Sm is a complex example of shape coexistence rather than a critical point nucleus.
Garrett
P E
PE
Department of Physics, University of Guelph, Guelph, Ontario, N1G2W1 Canada.
Kulp
W D
WD
Wood
J L
JL
Bandyopadhyay
D
D
Choudry
S
S
Dashdorj
D
D
Lesher
S R
SR
McEllistrem
M T
MT
Mynk
M
M
Orce
J N
JN
Yates
S W
SW