TY - JOUR
ID - Digital.CSIC
A1 - Aas, A. J.
A1 - Fogelberg, B.
A1 - García Borge, María José
A1 - Grant, I. S.
A1 - Gulda, K.
A1 - Hagebø, E.
A1 - Hoff, P.
A1 - Kurcewicz, W.
A1 - Kvasil, J.
A1 - Lindroth, A.
A1 - Løvhøiden, G.
A1 - Mach, H.
A1 - Mackova, A.
A1 - Martínez, T.
A1 - Rubio, Berta
A1 - Sánchez-Vega, M.
A1 - Smith, J. F.
A1 - Taín, José Luis
A1 - Taylor, R. B. E.
A1 - Tengblad, Olof
A1 - Thorsteinsen, T. F.
Y1 - 1999-08-02
SN - 0375-9474
UR - http://hdl.handle.net/10261/10057
N2 - The fast timing ???(t) method has been used to measure lifetimes of the low-lying levels in Th-231 populated in the ?- decay of Ac-231. The half-life of the K-? = 5/2(-) band-head at 185.7-keV was measured as T(1/2) = 1073(79) ps, yielding D-0 = 1.76(8) x 10(-2) e·fm and 1.65(6) x 10(-2) e·fm for the El transitions to the 7/2(+) and 5/2(+) members respectively of the K-? = 5/2(+) ground state band. Furthermore, T(1/2) ? 74 ps and ? 74 ps were measured for the K-? = 3/2(+) and 1/2(+) bandheads at 221.4- and 247.6-keV, and T-1/2 = 503(12) ps and 98(36) ps for the 1/2(-) and 3/2(-) states at 554.7- and 593.6-keV, members of the K-? = 1/2(-) band. The latter results consistently yield D(0) values of the order of 1.1 x 10-2 e·fm for three transitions connecting the K-? = 1/2(±) bands. The observed transition rates have been interpreted within the quasiparticle-phonon model with the inclusion of Coriolis coupling.
PB - Elsevier
KW - ?-
KW - Ac-231
KW - B(XL)
KW - Deduced Th-231 levels
KW - Fast-timing ???(t) method
KW - Measured E?, I?, ?-? coincidences, T(1/2)
KW - [PACS] ? transitions and level energies
KW - [PACS] Collective levels
KW - [PACS] Electromagnetic transitions
KW - [PACS] Lifetimes, widths
KW - [PACS] Properties of nuclei; nuclear energy levels
KW - [PACS] Properties of specific nuclei listed by mass ranges (A ? 220 )
KW - Quasiparticle-plus-phonon model
KW - Radioactivity
KW - Rotational bands
T1 - Quenched E1 transition rates in Th-231
ER -