Observation of 54Ni: cross-conjugate symmetry in f7/2 mirror energy differences.
Gamma decays from excited states up to Jpi=6+ in the N=Z-2 nucleus 54Ni have been identified for the first time. Level energies are compared with those of the isobars 54Co and 54Fe and of the cross-conjugate nuclei of mass A=42. The good but puzzling f7/ cross-conjugate symmetry in mirror and triplet energy differences is analyzed. Shell model calculations reproduce the new data but the necessary nuclear charge-dependent phenomenology is not fully explained by modern nucleon-nucleon potentials.
Gadea
A
A
INFN Laboratori Nazionali di Legnaro, Italy.
Lenzi
S M
SM
Lunardi
S
S
Mărginean
N
N
Zuker
A P
AP
de Angelis
G
G
Axiotis
M
M
Martínez
T
T
Napoli
D R
DR
Farnea
E
E
Menegazzo
R
R
Pavan
P
P
Ur
C A
CA
Bazzacco
D
D
Venturelli
R
R
Kleinheinz
P
P
Bednarczyk
P
P
Curien
D
D
Dorvaux
O
O
Nyberg
J
J
Grawe
H
H
Górska
M
M
Palacz
M
M
Lagergren
K
K
Milechina
L
L
Ekman
J
J
Rudolph
D
D
Andreoiu
C
C
Bentley
M A
MA
Gelletly
W
W
Rubio
B
B
Algora
A
A
Nacher
E
E
Caballero
L
L
Trotta
M
M
Moszyński
M
M