Search for stable octupole deformation in Fr-225
Search for stable octupole deformation in Fr-225
Levels in Fr-225 have been studied by gamma-ray and conversion-electron spectroscopy following the beta-decay of Rn-225 and by the Ra-226(t,alpha)Fr-225 single-proton-pickup reaction. Multipolarities were obtained for ~ 50 gamma-transitions, and a level scheme was established in which definite spin-parity values were determined for over 20 of the 48 levels. Although low-lying rotational bands of both parities exist for K = 1/2 and K = 3/2, there is no experimental evidence to claim these are parity doublets. E1 strengths connecting the K-π = 3/2(±) bands are intermediate between those for nuclides which are reflection symmetric and those claimed to be octupole deformed. The (t,α) cross sections are in better agreement with those predicted for the reflection-symmetric case than with those from an octupole-deformed description. These observations may be confirming theoretical predictions that octupole correlations are important in Fr-225, but that there is no large stable octupole deformation.
This work was performed under the auspices of the Natural Sciences and Engineering Research Council of Canada, the German Bundesministerium ftir Forschung und Technologie, the Norges Almenvitenskapelige Forskningsrhd, the Polish Committee for Scientific Research, the US Department of Energy by Lawrence Livermore National Laboratory under Contract W-7045-ENG-48 and the Spanish CICYT under contract AEN94-0833-C02-02.
52 pages, 11 figures, 10 tables.-- PACS nrs.: 23.20.−g; 23.20.Lv; 25.45.Hi; 25.55.−e; 27.90.+b.
Peer reviewed
Mini-orange spectrometer, Fr-225 deduced levels, (t,α) Q-value, [PACS]γ transitions and level energies, Radioactivity: Rn-225(beta) [from Th-232(p,5p3n), mass separation], γγ-coincidences, eγ-coincidences, [PACS] Transfer reactions, Rn-225(beta) [from Th-232(p,5p3n), mass separation] [Radioactivity], A ≥ 220 [[PACS] Properties of specific nuclei listed by mass ranges], [PACS] Electromagnetic transitions, Measured σ(E(α)), Magnetic spectrograph, Ra-226(t,α), E=18 MeV [Nuclear reactions], Measured E(γ), I-γ, E(epsilon), I(ce), T-1/2, Nuclear reactions: Ra-226(t,α), E=18 MeV, [PACS] 3H-, 3He-, and 4He- induced reactions, ICC, multipolarities, I-π, rotational bands, E1 transition strengths, Ge and Si(Li) detectors, [PACS] Properties of specific nuclei listed by mass ranges: A ≥ 220
Mini-orange spectrometer, Fr-225 deduced levels, (t,α) Q-value, [PACS]γ transitions and level energies, Radioactivity: Rn-225(beta) [from Th-232(p,5p3n), mass separation], γγ-coincidences, eγ-coincidences, [PACS] Transfer reactions, Rn-225(beta) [from Th-232(p,5p3n), mass separation] [Radioactivity], A ≥ 220 [[PACS] Properties of specific nuclei listed by mass ranges], [PACS] Electromagnetic transitions, Measured σ(E(α)), Magnetic spectrograph, Ra-226(t,α), E=18 MeV [Nuclear reactions], Measured E(γ), I-γ, E(epsilon), I(ce), T-1/2, Nuclear reactions: Ra-226(t,α), E=18 MeV, [PACS] 3H-, 3He-, and 4He- induced reactions, ICC, multipolarities, I-π, rotational bands, E1 transition strengths, Ge and Si(Li) detectors, [PACS] Properties of specific nuclei listed by mass ranges: A ≥ 220
selected citations These citations are derived from selected sources.This is an alternative to the "Influence" indicator, which also reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically).0 popularity This indicator reflects the "current" impact/attention (the "hype") of an article in the research community at large, based on the underlying citation network.Average influence This indicator reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically).Average impulse This indicator reflects the initial momentum of an article directly after its publication, based on the underlying citation network.Average
Citations provided by BIP!Popularity provided by BIP!