The rotational structure of 227Ra

Egidy, T. von; Barreau, G.; Börner, H. G.; Davidson, W.F.; Larysz, J.; Warner, D.D.; Assche, P.H.M. Van; Nybo, Kristie; Thorsteinsen, T.F.; Løvhøiden, G.; Flynn, E.R.; Cizewski, J. A.; Sheline, Raymond K.; Decman, D.J.; Burke, D. G.; Sletten, G.; Kaffrell, Ν.; Kurcewicz, W.; Björnstad, T.; Nyman, G.

doi:10.1016/0375-9474(81)90386-9

Cited by 40 publications

(9 citation statements)

References 38 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…These results yielded halflives of 23 • 1 s for the previously unknown isotope 227Rn and 2.52_ 0.05 rain for 227Fr. The latter value is in agreement with the previously accepted value [7] of 2.47 _+ 0.03 min, thereby supporting the assignment of the activities. 227Rn _.~227Fr _~227Ra …”

Section: Mass 227supporting

confidence: 91%

See 1 more Smart Citation

New isotope227Rn and revised halflives for223Rn and226Rn

Borge

Burke

Calaprice

et al. 1986

Z. Physik A - Atomic Nuclei

Self Cite

View full text Add to dashboard Cite

Neutron-rich isotopes of radon, produced by spallation reactions in a ThC2 target and selected chemically, were mass-separated and used as samples for radiation counting experiments. Assignments of the activities to radon isotopes were confirmed by genetic relationships to the previously known francium daughters. The halflife for the new isotope 227Rn is 23_+ 1 s and that for 226Rn is 7.4_+ 0.1 min. X-rays, 7-rays, and conversion electrons from the 223Rn activity were measured. The decay patterns of K X-rays and known gamma transitions in the 223Fr daughter yield a halflife of 23.2___ 0.4 min for 22aRn, in contrast to the value of 43 + 5 rain reported earlier. Energies, intensities, and likely multipolarities for the most prominent gamma transitions in the ZZ3Rn ~ 223Fr decay are presented.

show abstract

Section: Mass 227supporting

confidence: 91%

“…The hitherto unknown isotope 22VRn would be expected to//-decay to 2Z7Fr, which has a half-life of 2.47+_0.03 rain [7] for/3-decay to 42.2 rain 227Ra [8].…”

Section: Mass 227mentioning

confidence: 99%

New isotope227Rn and revised halflives for223Rn and226Rn

Borge

Burke

Calaprice

et al. 1986

Z. Physik A - Atomic Nuclei

Self Cite

View full text Add to dashboard Cite

show abstract

“…227 Ra previously proposed [22,23] and identied the contaminating transitions, including the overlapping -transitions from the 227 Rn! 227 Fr decay.…”

Section: -Coincidencesmentioning

confidence: 99%

“…However, this mixing does not seem to aect the equivalent E1 transitions (of energy 64.3 and 88.3 keV) from the lower state of the same (K = 3=2 ) PD band which populate these two 5=2 + states with the fast and slow rates as`expected' for the intra-and inter-PD transitions, respectively. As part of the explanation, note that the K = 3=2 PD band classied as 3/2[761] was found [19,23] to be strongly mixed with other bands by the Coriolis interaction. In order to discuss the aforementioned issues in the framework of our theoretical calculations, a brief description of the model is given below.…”

Section: Quenched E1 Transitions; E1 Transitions Outside Parity-doublmentioning

confidence: 99%

Enhanced and quenched B(E1) transition rates between parity doublet bands in 227Ra

et al. 1996

Self Cite

View full text Add to dashboard Cite

The fast timing (t) method has been used to measure level lifetimes in the parity doublet bands in 227 Ra populated in the decay of 227 Fr. In particular, T 1=2 = 254(9) ps, 236(30) ps, 41 ps, and 16(13) ps have been measured for the 3/2 and 5/2 members of the K = 3/2 band and for the 1/2 and 3/2 members of the K = 1/2 band, respectively. These results indicate surprisingly fast B(E1) rates in this octupole transitional nucleus with the average jD 0 j value of 0.11 efm for the K = 1/2 band and jD 0 j=0.10 efm for K = 3/2 band. The general enhancement (and occasional quenching) of E1 i n tra-doublet and some enhanced extra-doublet transitions in 227 Ra are interpreted within the quasiparticleplus-phonon model with the inclusion of Coriolis coupling. Similar calculations, performed for 223 Ra, are found to be in good agreement with the experimental data.

show abstract

“…Approaches which treat the particlecore interaction in the intrinsic frame of reference stress on the role played by the Coriolis interaction, through the decoupling parameter, in determining the energy splitting of the parity partner states with K = 1/2. For example, in 227 Ra the decoupling factor is quite high (0.7) [17]. In the laboratory frame we identified the interaction which determine the energy parity split.…”

Section: Discussionmentioning

confidence: 99%

Coherent state model extension for the description of positive and negative parity bands in even-odd nuclei

Râduţâ

Raduta²,

Faessler

2009

Phys. Rev. C

View full text Add to dashboard Cite

A particle-core Hamiltonian is used to describe the lowest parity partner bands K π = 1/2 ± in 237 U and 239 Pu. The quadrupole and octupole boson Hamiltonian associated to the core is identical to the one previously used for the description of four positive and four negative parity bands in the neighboring even-even isotopes. The single particle space for the odd nucleon consists of three spherical shell model states, two of positive and one of negative parity. The particle-core Hamiltonian consists of four terms: a quadrupole-quadrupole, an octupole-octupole, a spin-spin and a rotationalÎ 2 interaction, withÎ denoting the total angular momentum. The parameters involved in the particle-core coupling Hamiltonian were fixed by fitting four particular energies in the two bands. The calculated excitation energies are compared with the corresponding experimental data as well as with those obtained with other approaches. Also, we searched for some signatures for a static octupole deformation in the considered odd isotopes.PACS numbers: 21.10. Re,21.60.Ev,27.80.+w,27.90.+b The coherent state model (CSM)[1] describes in a realistic fashion three interacting bands, ground, beta and gamma, in terms of quadrupole bosons. The formalism was later extended [2,3,4,5,6,7] by considering the octupole degrees of freedom. The most recent extension describes eight rotational bands, four of positive and four of negative parity. Observables like excitation energies, intraband E2 and interband E1, E2 and E3 reduced transition probabilities have been calculated and the results were compared with the corresponding experimental data. The formalism works well for both near spherical and deformed nuclei excited in low and high angular momentum states. Indeed, we considered all states with J ≤ 30 in both, the positive and the negative parity bands. Signatures for a static octupole deformation in ground as well as in excited bands have been pointed out in several even-even nuclei.The aim of this paper is to extend CSM for the evenodd nuclei which exhibit both quadrupole and octupole deformation. Thus, we consider a particle-core Hamiltonian:where H sp is a spherical shell model Hamiltonian associated to the odd nucleon, while H core is a phenomenological Hamiltonian which describes the collective motion of the core in terms of quadrupole and octupole bosons. This term is identical to that used in Ref.[7] to describe eight rotational bands in even-even nuclei. The two subsystems interact with each other by H pc , which has the following expression:b † λµ denotes the components of the λ-pole (with λ=2,3) boson operator. The term j J is similar to the spin-orbit interaction from the shell model and expresses the interaction between the angular momenta of the odd-particle and the core. The last term is due to the rotational motion of the whole system, I denoting the total angular momentum of the particle-core system. The core states are described by eight sets of mutually orthogonal functions, obtained by projecting out the angular momentum ...

show abstract

The rotational structure of 227Ra

Cited by 40 publications

References 38 publications

New isotope227Rn and revised halflives for223Rn and226Rn

New isotope227Rn and revised halflives for223Rn and226Rn

Enhanced and quenched B(E1) transition rates between parity doublet bands in 227Ra

Coherent state model extension for the description of positive and negative parity bands in even-odd nuclei

Contact Info

Product

Resources

About