K isomers in 254No: probing single-particle energies and pairing strengths in the heaviest nuclei.
We have identified two isomers in 254No, built on two- and four-quasiparticle excitations, with quantum numbers K pi = 8- and (14+), as well as a low-energy 2-quasiparticle Kpi = 3+ state. The occurrence of isomers establishes that K is a good quantum number and therefore that the nucleus has an axial prolate shape. The 2-quasiparticle states probe the energies of the proton levels that govern the stability of superheavy nuclei, test 2-quasiparticle energies from theory, and thereby check their predictions of magic gaps.
Tandel
S K
SK
Department of Physics, University of Massachusetts Lowell, Lowell, Massachusetts 01854, USA.
Khoo
T L
TL
Seweryniak
D
D
Mukherjee
G
G
Ahmad
I
I
Back
B
B
Blinstrup
R
R
Carpenter
M P
MP
Chapman
J
J
Chowdhury
P
P
Davids
C N
CN
Hecht
A A
AA
Heinz
A
A
Ikin
P
P
Janssens
R V F
RV
Kondev
F G
FG
Lauritsen
T
T
Lister
C J
CJ
Moore
E F
EF
Peterson
D
D
Reiter
P
P
Tandel
U S
US
Wang
X
X
Zhu
S
S