High-K, t1/2 = 1.4(1)ms, isomeric state inLr255

Authors :: A. P. Kabachenko
Magne Guttormsen
Neil Rowley
D. Curien
N. U. H. Syed
F. Khalfallah
M. L. Chelnokov
O. Dorvaux
Alexey Belozerov
A. G. Popeko
M. Venhart
Louise Stuttge
Francis Hanappe
Andreas Görgen
A. Shutov
A. I. Svirikhin
A. Lopez-Martens
A. Minkova
S. Saro
S. Antalic
André Larsen
B. Gall
M. Rousseau
V. I. Chepigin
V. A. Gorshkov
Ch. Briançon
K. Hauschild
Ch. Theisen
O. N. Malyshev
Alexander Yeremin
Sunniva Siem
Source :: Physical Review C. 78
Publication Year :: 2008
Publisher :: American Physical Society (APS), 2008.
Abstract: An isomeric state in {sup 255}Lr with a half-life of t{sub 1/2} = 1.4(1) ms and E{sub x}>720-keV has been observed for the first time using the GABRIELA setup at the focal plane of the VASSILISSA separator. Based on its K-forbiddeness, the configuration of the state is most probably formed by coupling the valence proton to a two quasiparticle neutron excitation. Possible three quasiparticle configurations are discussed.