2024-03-29T13:33:26Zhttp://digital.csic.es/dspace-oai/requestoai:digital.csic.es:10261/112302020-06-16T11:39:51Zcom_10261_61com_10261_4com_10261_135col_10261_314col_10261_388
Persistence of octupole correlations in Ra-231
Fraile, Luis M.
García Borge, María José
Mach, H.
Boutami, Rafik
Aas, A. J.
Fogelberg, B.
García Raffi, Luis M.
Grant, I. S.
Gulda, K.
Hagebø, E.
Kurcewicz, W.
Kvasil, J.
López, M. J.
Løvhøiden, G.
Martínez Pérez, Trinitario
Rubio, Berta
Taín, José Luis
Tengblad, Olof
Radioactivity, Fr-231(87)[from U-238(92)(p,6p2n) mass separation]
Measured E gamma, I gamma, I(CE), gamma-gamma coincidences
Gamma-e(-) coincidences, T-1/2
Deduced Ra-231(88) levels, ICC multipolarities, spin-parities, rotational bands, B(XL)
Advanced time delayed beta gamma gamma(t) method
Quasiparticle-plus-phonon model
Ge, Si(Li), BaF2 detectors
MINI-ORANGE spectrometer
[PACS] Properties of specific nuclei listed by mass ranges: A ≥ 220
[PACS] Collective levels
[PACS] Lifetimes, widths
[PACS] Electromagnetic transitions
38 pages, 8 tables, 9 figures.-- PACS nrs.: 23.20.-g; 21.10.Tg; 21.10.Re; 27.90.+b.-- Printed version published Apr 9, 2001.
The structure of Ra-231, the heaviest odd Ra nucleus currently accessible for detailed spectroscopic investigation, has been studied in the beta (-) decay of Fr-231. The main purpose has been to verify whether fast B(E1) rates and significant octupole correlations recently established in Ra-229 persist in Ra-231. The excited stares in Ra-231 have been determined for the first time. Spins and parities have been deduced from conversion electron measurements, while level half-lives in the ps and ns ranges have been measured with the Advanced Time Delayed beta gamma gamma (t) method. The moderately fast B(E1) rates found For transitions connecting the lowest-lying K-pi = 5/2(+/-) and K-pi = 1/2(+/-) hands, reveal the persistence of octupole collective effects in Ra-231, although the B(E1) rates are lower than in Ra-229. These findings reinforce the differences in the B(E1) systematics between isotonic Ra and Th nuclei.
This work was partially supported by the Spanish CICYT “Plan Nacional de Altas Energías” (under contracts AEN96-1662 and AEN96-1679), the Swedish Natural Science Research Council, the Czech Republic Grant Agency (under grant 202/99/1718) and the Polish Scientific Research Committee. L.M. Fraile would like to thank the OSIRIS group at Studsvik in Sweden for their generous hospitality and the Margit & Folke Pehrzon Foundation for the financial support for his stay at Studsvik.
Peer reviewed
2009-03-04T14:03:13Z
2009-03-04T14:03:13Z
2001-03-19
artículo
http://purl.org/coar/resource_type/c_6501
Nuclear Physics A 686(1-4): 71–108 (2001)
0375-9474
http://hdl.handle.net/10261/11230
10.1016/S0375-9474(00)00572-8
en
http://dx.doi.org/10.1016/S0375-9474(00)00572-8
none
503829 bytes
application/pdf
Elsevier