Band structure in the neutron-rich lanthanide nucleusNd152. II. Allowed andK-forbidden transitions from the negative-parity bands

The wobbling spectrum of [Formula: see text]Lu is described through a novel approach, starting from a triaxial rotor model within a semi-classical picture, and obtaining a new set of equations for all four rotational bands that have wobbling character. Redefining the band structure in the present model is done by adopting the concepts of Signature Partner Bands and Parity Partner Bands. Indeed, describing a wobbling spectrum in an even–odd nucleus through signature and parity quantum numbers is an inedited interpretation of the triaxial super-deformed bands.

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Band structure of odd-mass lanthanum nuclei

International Journal of Modern Physics E ◽

10.1142/s0218301314500207 ◽

2014 ◽

Vol 23 (04) ◽

pp. 1450020

Author(s):

Deepti Sharma ◽

Preeti Verma ◽

Suram Singh ◽

Arun Bharti ◽

S. K. Khosa

Keyword(s):

Band Structure ◽

Shell Model ◽

Nuclear Structure ◽

Transition Probabilities ◽

Theoretical Data ◽

Negative Parity ◽

Projected Shell Model ◽

Experimental Feature ◽

Reduced Transition Probabilities ◽

Structure Properties

Negative parity energy states in 121–131 La have been studied using Projected Shell Model (PSM). Some nuclear structure properties like yrast spectra, back-bending in moment of inertia, reduced transition probabilities and band diagrams have been described. The experimental feature of the co-existence of prolate–oblate shapes in 125–131 La isotopes has been satisfactorily explained by PSM results. Comparison of the theoretical data with their experimental counterparts has also been made. From the calculations, it is found that the yrast states arise because of multi-quasiparticle states.

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Band-structure enhancement of the indirect forbidden transitions

Physical Review B ◽

10.1103/physrevb.20.5292 ◽

1979 ◽

Vol 20 (12) ◽

pp. 5292-5296 ◽

Cited By ~ 8

Author(s):

J. Camassel ◽

J. Pascual ◽

H. Mathieu

Keyword(s):

Band Structure ◽

Forbidden Transitions ◽

Structure Enhancement

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Influence of forbidden transitions on the gain-band structure of XeCl molecules

Soviet Journal of Quantum Electronics ◽

10.1070/qe1992v022n04abeh003437 ◽

1992 ◽

Vol 22 (4) ◽

pp. 334-336

Author(s):

Viktor T Platonenko ◽

M K Shayakhmetova

Keyword(s):

Band Structure ◽

Forbidden Transitions

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A study of high spin states in 151Gd

Canadian Journal of Physics ◽

10.1139/p77-098 ◽

1977 ◽

Vol 55 (7-8) ◽

pp. 690-713 ◽

Cited By ~ 8

Author(s):

H. J. Smith ◽

M. W. Johns ◽

G. Løvhøiden ◽

J. V. Thompson ◽

J. C. Waddington ◽

...

Keyword(s):

Band Structure ◽

Rotational Band ◽

Gamma Ray ◽

Level Structure ◽

Negative Parity ◽

Angular Distributions ◽

Spin States ◽

High Spin States ◽

Conversion Coefficients ◽

Coincidence Measurements

States in the transitional nucleus, 151Gd, excited by the (α,2n) reaction have been studied by gamma-ray and conversion electron measurements. Gamma-ray energies, intensities, excitation functions, and γ–γ coincidence measurements were used to establish the levels populated. Angular distributions involving measurements at seven angles from 0° to 90° and K-conversion coefficients have been used to make spin and parity assignments.The El character of the 65, 79, 340, 358, 406, and 462 keV transitions, which in the absence of K-conversion data had been tacitly assumed to be M1 by earlier workers leads to a significant revision of their parity assignments and interpretation of the level structure. The negative parity states at 1210, 1463, 1726, 2004, 2295, 2600, 2915, and 3237 keV form a well-developed rotational band based on the 11/2− [505] state at 1210 keV. The properties of this band in this nucleus are compared with those of the same band in a number of nearby nuclei. Two non-interacting negative parity bands with states at 0(7/2−), 706(11/2−), 1435(15/2−), 2078(19/2−), and 379(9/2−), 902(13/2−), 1511(17/2−), 2297(21/2−), respectively, have been found, as well as a number of other negative parity states of spin 7/2, 9/2, and 13/2. A complex positive band structure involving states at 784(11/2+), 852(13/2+), 1116(13/2+), 1346(17/2+), 1364(15/2+), 1677(17/2+), 1851(19/2+), 1853(21/2+), 2197(21/2+), 2325(23/2+), and 2405(25/2+) has been identified. By using a somewhat unusual set of parameters, we have been able to approach a description for the positive parity states in terms of the triaxial model of Meyer-ter-Vehn.

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Band Structure in 21Ne

Canadian Journal of Physics ◽

10.1139/p72-176 ◽

1972 ◽

Vol 50 (12) ◽

pp. 1286-1294 ◽

Cited By ~ 10

Author(s):

A. A. Pilt ◽

R. H. Spear ◽

R. V. Elliott ◽

D. T. Kelly ◽

J. A. Kuehner ◽

...

Keyword(s):

Angular Distribution ◽

Band Structure ◽

Linear Polarization ◽

Negative Parity ◽

Mixing Ratios ◽

Decay Branch ◽

Nilsson Model ◽

Γ Rays ◽

Model Evidence ◽

Γ Ray

The 18O(α,nγ) reaction at α-particle bombarding energies of 5.2 and 6.1 MeV was used to study the levels in 21Ne below 4 MeV excitation. A combination of γ-ray angular distribution and linear polarization measurements using a single crystal Ge(Li) polarimeter confirmed the spins and parities of the 1747 and 2867 keV states to be 7/2+ and 9/2+ respectively and assigned negative parity to the J = 3/2 level at 3663 keV and J = 5/2 level at 3886 keV. The state at 3735 keV was shown to have Jπ = 5/2+. Values of the multipole mixing ratios of γ rays deexciting these states were found to be consistent with previous measurements. A γ–γ coincidence experiment revealed the existence of a (1.8 ± 0.7)% decay branch of the 3886 keV level to the 2790 keV level. The results are interpreted in terms of the Nilsson model. Evidence for the existence of a Kπ = 1/2− band based on a hole in the 1p1/2 shell is given.

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Recent Radiative and Collisional Atomic Data of Astrophysical Interest

International Astronomical Union Colloquium ◽

10.1017/s0252921100107596 ◽

1988 ◽

Vol 102 ◽

pp. 129-132

Author(s):

K.L. Baluja ◽

K. Butler ◽

J. Le Bourlot ◽

C.J. Zeippen

Keyword(s):

Mass Production ◽

Bound States ◽

Physical Models ◽

Impact Excitation ◽

Electron Impact Excitation ◽

Atomic Data ◽

Isoelectronic Sequence ◽

Astrophysical Interest ◽

Radiative Transitions ◽

Forbidden Transitions

SummaryUsing sophisticated computer programs and elaborate physical models, accurate radiative and collisional atomic data of astrophysical interest have been or are being calculated. The cases treated include radiative transitions between bound states in the 2p4and 2s2p5configurations of many ions in the oxygen isoelectronic sequence, the photoionisation of the ground state of neutral iron, the electron impact excitation of the fine-structure forbidden transitions within the 3p3ground configuration of CℓIII, Ar IV and K V, and the mass-production of radiative data for ions in the oxygen and fluorine isoelectronic sequences, as part of the international Opacity Project.

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