A study of high spin states in 151Gd

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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Levels in 148Tb excited by the (6,7Li,xn) and (10B,xn) reactions

Canadian Journal of Physics ◽

10.1139/p79-047 ◽

1979 ◽

Vol 57 (3) ◽

pp. 358-367 ◽

Cited By ~ 6

Author(s):

N. C. Singhal ◽

M. W. Johns

Keyword(s):

High Spin ◽

Internal Conversion ◽

Gamma Ray ◽

Angular Distributions ◽

Spin States ◽

High Spin States ◽

Internal Conversion Coefficients ◽

Conversion Coefficients ◽

Γ Ray ◽

Coincidence Measurements

High spin slates in 148Tb have been excited by means of 144Sm(6Li,2n), 144Sm(7Li,3n), and 142Nd(10B,4n) reactions and studied by γ-ray and electron measurements. Gamma-ray singles, excitation functions, angular distributions, internal conversion coefficients, and γ–γ coincidence measurements have been made. A seven-fold gamma–gamma cascade feeding the 9+ isomeric state in 148Tb and originating in a level 4137 keV above that state is strongly excited. The spin and parity assignments are made on the basis of angular distribution and internal conversion coefficients. On the basis of these measurements, the 1006 keV transition is E3 in character; the half-life of the 1006 keV (12−) level is established to be 25 ± 2 ns.These experiments also confirm the existence of a number of high spin states in 148Gd seen by earlier workers.

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High spin states in 96Tc populated through the (α,n) reaction

Canadian Journal of Physics ◽

10.1139/p80-029 ◽

1980 ◽

Vol 58 (2) ◽

pp. 174-190 ◽

Cited By ~ 3

Author(s):

H. A. Mach ◽

M. W. Johns ◽

J. V. Thompson

Keyword(s):

Theoretical Model ◽

High Spin ◽

Spin Structure ◽

Gamma Ray ◽

Angular Distributions ◽

Spin States ◽

High Spin States ◽

Gamma Coincidence ◽

Electron Conversion ◽

Conversion Coefficients

High spin states of 96Tc populated by the (α,n) reaction using alpha beams from 13 to 27 MeV have been studied. Gamma-ray energies and intensities, gamma–gamma coincidence probabilities, gamma-ray angular distributions, and electron conversion coefficients were determined at 18 MeV. In addition, some results taken at 14 MeV are reported.The high spin structure observed in this work includes the following levels: 49.3(6+), 318.8(6+), 574.7(7+), 926.9(9+), 946.5(8+), 1062.1(8+), 1138.8(8+), 1447.2(9+), 1702.8(10+), 1861.6(9+), 1922.3(11+), 2147.5(11+), 2213.5(10(+)), 2317.2(12+), 2396.8(11(+)), 2599.0((13)+), 2642.4((14)+), and 3020.1(12(+)).These experiments also clarify and extend the information obtained by previous workers. In particular, evidence is adduced for low-lying states at 0.0(7+), 34.3(4+), 45.3(5+), 120.3(3−), 177.0(5+), 226.2(2−), 227.0(4+), and 254.3(3+).The work identifies many other states of intermediate energy.Attenuation coefficients for states in 96Tc are calculated using a theoretical model.

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A Kπ = 0− Octupole Band in 150Sm

Canadian Journal of Physics ◽

10.1139/p75-156 ◽

1975 ◽

Vol 53 (13) ◽

pp. 1229-1235 ◽

Cited By ~ 7

Author(s):

J. V. Thompson ◽

M. W. Johns ◽

J. C. Waddington

Keyword(s):

High Spin ◽

Conversion Electron ◽

Gamma Ray ◽

Angular Distributions ◽

Spin States ◽

High Spin States ◽

Gamma Coincidence

A study of the 148Nd(α, 2n)150Sm reaction has revealed the high spin states of a Kπ = 0− octupole band, the members of which become the yrast levels above spin 12. Gamma ray angular distributions, gamma–gamma coincidence, and conversion electron studies have established the levels of the octupole band at 1764.6(7−), 2232.1(9−), 2744.0(11−), and tentatively at 3293.0(13−) keV.

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High spin structure of 155Dy

HNPS Proceedings ◽

10.12681/hnps.2378 ◽

2019 ◽

Vol 3 ◽

pp. 114

Author(s):

C. T. Papadopoulos ◽

R. Vlastou ◽

M. Serris ◽

C. A. Kalfas ◽

N. Fotiades ◽

...

Keyword(s):

High Spin ◽

Beam Energy ◽

Spin Structure ◽

Negative Parity ◽

Spin States ◽

Detailed Structure ◽

Strongly Coupled ◽

Rotational Bands ◽

High Spin States ◽

Coincidence Measurements

High spin states in 155Dy have been studied by γ-γ coincidence measurements via the 124Sn(36S, 5n)155Dy reaction at a beam energy of 155 MeV. Eight rotational bands have been populated and observed up to high spin (I<91/2).The band features have been analysed within the framework of the cranked shell model. The Ì13/2 neutron alignments and the h11/2 proton alignments are discussed. B(M1)/B(E2) ratios have also been extracted for the strongly coupled bands to deduce further information on the detailed structure of these bands. For the highest states (above spin 30) of the negative parity bands an irregularity in y-ray energies appears which is discussed in terms of band termination.

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Study of high spin states in 149Tb observed by the (10B,3n) reaction

Canadian Journal of Physics ◽

10.1139/p79-269 ◽

1979 ◽

Vol 57 (11) ◽

pp. 1959-1968 ◽

Cited By ~ 12

Author(s):

N. C. Singhal ◽

M. W. Johns ◽

J. V. Thompson

Keyword(s):

High Spin ◽

Energy Levels ◽

Negative Parity ◽

Positive Parity ◽

Angular Distributions ◽

Spin States ◽

Core Nucleus ◽

High Spin States ◽

Parity Band ◽

Positive Parity Band

Energy levels in 149Tb have been studied by the 142Nd (10B,3n) reaction using 54 MeV 10B beams from the McMaster University FN accelerator. Excitation functions, angular distributions, prompt γ–γ coincidence, electron conversion, and linear polarization measurements were obtained. On the basis of these measurements we have identified two rotaition-aligned πh11/2 bands, a negative parity band up to spin 27/2−, and a positive parity band up to spin 27/2+. The energy spacings between levels in these bands strongly resemble those in the ground state and the 3− octupole band of the adjacent 148Gd core nucleus. Other high spin positive parity states up to spin of 41/2 are also observed. These high spin states show some evidence of rotational structure in 14 9Tb.

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Investigation of the level structure of 90Nb nucleus using the shell model

Nukleonika ◽

10.2478/nuka-2019-0014 ◽

2019 ◽

Vol 64 (4) ◽

pp. 113-116

Author(s):

Wu Yi-Heng ◽

Yang Dong ◽

Ma Ke-Yan ◽

Luo Peng-Wei

Keyword(s):

Shell Model ◽

Level Structure ◽

Model Space ◽

Negative Parity ◽

Spin States ◽

Shell Closure ◽

Model Calculations ◽

High Spin States ◽

Single Neutron ◽

Subshell Closure

Abstract Shell model calculations have been carried out for 90Nb nucleus with the model space in which the valence protons occupy the f5/2, p3/2, p1/2, and g9/2 orbitals and the valence neutrons occupy the p1/2, g9/2, d5/2, and g7/2 orbitals. According to the calculated results, the negative parity is from the contribution of the proton of the f5/2, p3/2, and p1/2 orbits. The moderate spin states of 90Nb are mainly due to the excitation of protons from the f5/2 and p3/2 orbits to the p1/2 and g9/2 orbits across the Z = 38 subshell closure, and the high spin states arise from the excitation of a single neutron from the g9/2 orbit into the d5/2 orbit across the N = 50 shell closure.

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Negative-parity high-spin states and a possible magnetic rotation band inPr7659135

Physical Review C ◽

10.1103/physrevc.92.054325 ◽

2015 ◽

Vol 92 (5) ◽

Cited By ~ 5

Author(s):

Ritika Garg ◽

S. Kumar ◽

Mansi Saxena ◽

Savi Goyal ◽

Davinder Siwal ◽

...

Keyword(s):

High Spin ◽

Negative Parity ◽

Magnetic Rotation ◽

Spin States ◽

High Spin States ◽

Rotation Band

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A New Energy Level in 20Ne at 10·31 MeV

Australian Journal of Physics ◽

10.1071/ph640056 ◽

1964 ◽

Vol 17 (1) ◽

pp. 56 ◽

Cited By ~ 4

Author(s):

DG Sargood ◽

GD Putt

Keyword(s):

Energy Level ◽

Neutron Energy ◽

Gamma Ray ◽

Angular Distributions ◽

New Energy ◽

State Spin ◽

Gamma Decay ◽

Coincidence Measurements ◽

Made In

Neutron-gamma-ray coincidence measurements have been made in the reaction 19F(d,ny),oNe at bombarding energies between 500 and 700 keV. Time offlight determination of neutron energy indicates a new energy level in .oNe at lO� 31 �O' 07 MeV. From angular distributions of the neutrons, and observation of the gamma -decay spectrum of the 10.31 MeV state, spin and parity of 1 + are inferred for this state.

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